Unit 4

Unit 4: EPIDEMIOLOGY

‫‪English for the Students of Public Health‬‬

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‫آﺷﻨﺎﻳﻲ ﺑﺎ ﻣﺘﻦ ﻫﺎي درس‬ ‫درس ﭼﻬﺎر داراي ﺳﻪ ﻣﺘﻦ ﺟﺪاﮔﺎﻧﻪ اﺳﺖ‪ (1):‬ﻣﺘﻦ اﺻﻠﻲ)‪(Reading‬؛ )‪(2‬ﻣﺘﻦ ﺧﻮاﻧﺪﻧﻲ‬ ‫اﺿﺎﻓﻲ )‪(Further Reading‬؛ )‪(3‬ﻣﺘﻦ ﻛﺎﻣﻞ ﻛﺮدﻧﻲ)‪.(Cloze‬‬ ‫ﻣﺘﻦ اﺻﻠﻲ ﺗﺤﺖ ﻋﻨﻮان ‪Control of Communicable and Certain‬‬ ‫‪ Noninfectious Disease: Definitions‬ﺑﻪ ﺗﻌﺮﻳﻒ ﻣﻬﻢ ﺗﺮﻳﻦ اﺻﻄﻼﺣﺎت راﻳﺞ در‬ ‫ﻣﺘﻮن اﭘﻴﺪﻣﻴﻮﻟﻮژي ﻣﻲ ﭘﺮدازد‪.‬‬ ‫ﻣﺘﻦ ﺧﻮاﻧﺪﻧﻲ اﺿﺎﻓﻲ ﺗﺤﺖ ﻋﻨﻮان ‪ Diphteria‬ﺑﻴﻤﺎري دﻳﻔﺘﺮي و ﻋﻮاﻣﻞ اﭘﻴﺪﻣﻴﻮﻟﻮژي‬ ‫آن را ﺗﻮﺿﻴﺢ ﻣﻲ دﻫﺪ‪.‬‬ ‫ﻣﺘﻦ ﻛﺎﻣﻞ ﻛﺮدﻧﻲ ‪ Malaria‬ﻧﻘﺶ اﻃﻼﻋﺎت ﺑﻬﺪاﺷﺘﻲ ﭘﻴﺮاﻣﻮن ﺑﻴﻤﺎري ﺷﺎﻳﻊ ﻣﺎﻻرﻳﺎ‬ ‫ﻛﻪ ﺳﺎﻻﻧﻪ زﻧﺪﮔﻲ ﻫﺰاران اﻧﺴﺎن را در ﺟﻬﺎن ﻣﻲ ﮔﻴﺮد ﺑﻪ وﻳﮋه ﻧﻘﺶ ﺣﻘﻮق ﺧﺎﻧﻮاده ﻫﺎ و‬ ‫ﺟﻮاﻣﻊ در ﻛﺴﺐ اﻳﻦ اﻃﻼﻋﺎت در ﭘﻴﺸﮕﻴﺮي از ﺑﻴﻤﺎري را ﻣﻄﺮح ﻣﻲ ﺳﺎزد‪.‬‬ ‫ﻫﺪف ﻛﻠﻲ‪:‬‬ ‫آﺷﻨﺎﻳﻲ ﺑﺎ واژﮔﺎن و اﺻﻄﻼﺣﺎت ﻣﺮﺗﺒﻂ ﺑﺎ ﻣﻔﻬﻮم »اﭘﻴﺪﻣﻴﻮﻟﻮژي« و درك ﻣﻄﻠﺐ اﻳﻦ ﻣﺘﻦ و‬ ‫ﻣﺘﻮن ﻣﺸﺎﺑﻪ در اﻳﻦ زﻣﻴﻨﻪ‪.‬‬ ‫ﻫﺪف ﻫﺎي رﻓﺘﺎري‪:‬‬ ‫ﭘﺲ از ﻓﺮاﮔﻴﺮي اﻳﻦ درس ﺑﺎﻳﺪ ﺑﺘﻮاﻧﻴﺪ‪:‬‬ ‫‪ -1‬ﻣﻔﻬﻮم و ﻣﻌﻨﻲ ﻫﺮ ﻳﻚ از واژﮔﺎن ﻛﻠﻴﺪي زﻳﺮ را در ﺟﻤﻠﻪ ﺗﺸﺨﻴﺺ دﻫﻴﺪ‪:‬‬ ‫‪Function(n.), function(v.), essential(adj.), essential(n.), essentially,‬‬ ‫‪produce, product, production, productive, productivity, develop,‬‬ ‫‪development, source, result(n.), result(v.), expose, exposure, present,‬‬ ‫‪presence, express, transmit, transmission, association, direct, directly.‬‬ ‫‪ -2‬ﻣﺘﻦ اﺻﻠﻲ را ﻣﻄﺎﻟﻌﻪ و درك ﻛﻨﻴﺪ و ﺑﻪ ﺳﻮاﻻت ﻣﺮﺑﻮط ﺑﻪ ﻣﺘﻦ ﭘﺎﺳﺦ دﻫﻴﺪ‪.‬‬ ‫‪ -3‬ﺟﺎﻫﺎي ﺧﺎﻟﻲ ﻣﺘﻦ ﻛﺎﻣﻞ ﻛﺮدﻧﻲ)‪ (Cloze‬را ﺑﺎ اﺳﺘﻔﺎده از واژﮔﺎن داده ﺷﺪه ﺗﻜﻤﻴﻞ ﻛﻨﻴﺪ‪.‬‬ ‫‪ -4‬واژﮔﺎن ﺗﺨﺼﺼﻲ‪ ،‬اﺻﻄﻼﺣﺎت ‪ ،‬واژﮔﺎن ﻣﺮﻛﺐ و ﺟﻤﻠﻪ ﻫﺎي ﺳﺎده ﻳﺎ ﻣﺮﻛﺐ‪ ،‬ﭘﺎرﮔﺮاف ﻫﺎي‬ ‫ﻛﻮﺗﺎه ﺗﺨﺼﺼﻲ ﻣﺮﺑﻮط ﺑﻪ درس را ﺑﻪ ﻓﺎرﺳﻲ ﺗﺮﺟﻤﻪ ﻛﻨﻴﺪ‪.‬‬

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KEY WORDS: Before reading the TEXT, look through the following key words, and then do the KEY WORDS REVIEW.

Part I function n. [countable] the purpose that sth is made for, or the job that someone does: The function of a cash-machine is to provide people with cash when the bank is shut. | perform a function: In your new job you will be expected to

perform many different functions.

function v. 1 if sth functions, it works in the way it is supposed to: When the camera is functioning properly the green light comes on.

2 if sth functions in a particular way, it works in that way: Can you explain exactly how this new system will function?

3 not function if someone cannot function, they cannot do the activities that people normally do: She nurses people in their homes who are too ill to function alone. | function as sth phrasal verb to be or work as sth: Athens functioned as a centre of trade in the thirteenth century.

essential adj extremely important and necessary in order to do sth correctly or successfully: If you're going to hike in the mountains, strong boots are essential. | [+ for/to]: Good food and plenty of exercise are essential for a healthy life. | it is essential (that): It is essential that the oil is checked every 10,000km. | it is essential to do sth: It's essential to read the small print at the

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English for the Students of Public Health

bottom of any document.

essential n 1 [countable usually plural] sth that is important because it is necessary for life or for doing something: The charity provides homeless people with essentials like food and clothing. 2 the essentials [plural] the basic and most

important information or facts about a particular subject: the essentials of English grammar

essentially adv used when stating the most basic facts about sth: The two computer systems appear to be different but they are in fact essentially the same. | Hamid is essentially a moderate in politics.| [sentence adverb]: Essentially, the plan is worthwhile, but some changes will have to be made.

produce v 1 NATURALLY to grow sth or make it naturally: Canada produces high-quality wheat. | The pancreas produces insulin in the body. | More sun produces riper grapes.

2 RESULT to make sth happen or develop, or have a particular result or effect: New medicines are producing remarkable results in the treatment of cancer. | a remark which produced howls of protest | courses designed to produce better teachers 3 GOODS to make things to be sold: The factory produces an incredible 100 cars per hour. | Gas can be produced from coal.

charity= ‫ ﻧﻴﻜﻮﻛﺎري‬،‫اﺣﺴﺎن‬

homeless people= people

who have no home

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product n 1 [countable, uncountable] sth useful that is made in a factory, grown, or taken from nature: A product with a strong brand name is very important for good sales. | investing in product development | Demand for products like coal and steel is declining. | I'm allergic to dairy products.

2 the product of a) someone whose behavior, opinions etc can be explained by their experiences: Although he reacted violently against the society of his day, Nietsche's philosophy is a direct product of the Germany of that time.

b) sth that is a result of someone's actions or of good or bad conditions: Today's housing problems are the product of years of neglect.

production n 1 [uncountable] the process of making or growing things to be sold as products, or the amount that is produced: The production of consumer goods has increased throughout the world. | Smoking is banned in the factory's production areas. go into (full) production (=begin to be produced in large numbers): The prototype engines never went into production.

2 [uncountable] the act or process of making sth new, or of bringing sth into existence: The skin's natural production of oil slows down as we get older.

productive adj 1 producing or achieving a lot: Most of us are

ban= ،‫ﻣﻤﻨﻮع ﻛﺮدن‬ ‫ﻗﺪﻏﻦ ﻛﺮدن‬

prototype= the first model or design of sth from which other forms will be developed

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more productive in the morning. | productive land | a productive meeting (=having useful results) 2 producing goods, crops, or wealth: Increased demand means developing more productive capacity in the factory.

productivity n [uncountable] the rate at which goods are produced, and the amount produced, compared with the work, time, and money needed to produce them: Management is always seeking ways to increase worker productivity.

develop v 1 GROW to grow or gradually change into a larger, stronger, or more advanced state, or to make someone or sth do this: Children develop very rapidly. | [+ into]: James has developed into a charming young man. | [+ from]: In less than ten years it develops from a seed into a full-grown tree.

2 PLAN/PRODUCT to make a new idea, plan, or product become successful over a period of time: Scientists are developing new drugs to treat arthritis.

3 START TO HAVE to gradually begin to have a quality, illness, problem etc: Some alcoholics develop liver disease.

4 BECOME MORE ACTIVE to become more active or more of a problem, and therefore become more noticeable: Trouble is developing in the cities.

Epidemiology

development n 1 [uncountable] the gradual growth of sth, so that it becomes bigger or more advanced: an expert in child development | [+ of]: a course on the development of Greek thought

2 [countable] a new event or piece of news that is likely to have an effect on the present situation: recent political developments in the former Soviet Union

3 [countable] the act or result of making a product or design better and more advanced: There have been significant computer developments during the last decade.

source n [countable] 1 a thing, place, activity etc that you get sth from: They get their money from various sources. [+ of]: Milk is a very good source of calcium. For me, music is a great source of enjoyment.

2 the cause of sth, especially a problem, or the place where it starts [+ of]: We've found the source of the trouble - a faulty connection. | Two players have the same name, which has been the source of some confusion.

3 a person, book, or document that supplies you with information: List all your sources at the end of the essay. reliable sources: I've heard from reliable sources that the company is in trouble.

result n 1 HAPPENING BECAUSE OF STH [countable, uncountable] sth that happens or

reliable= ،‫ﻗﺎﺑﻞ اﻋﺘﻤﺎد‬ ‫ﻗﺎﺑﻞ اﻃﻤﻴﻨﺎن‬

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exists because of sth that happened before [+ of]: One result of the cold weather has been a sharp increase in our heating bill. | Ken's illness is the result of an accident at work. | The accident was a result of bad driving. | as a result (of) (=because of sth that has happened): As a result of the pilots' strike, all flights have had to be cancelled. | with the result that: Sara wasn't at school last week, with the result that she missed an important test. | be a direct result (of) (=caused by one thing only): High unemployment is a direct result of the recession. | end/final/net result (=the result at the end of a long process): The net result of all these changes is that people will pay more tax.

2 SCIENTIFIC TESTS [countable] the answers that are produced by a scientific study or test: Results show that men are twice as likely to suffer from stress as women. | We should have the result of your blood test tomorrow.

3 EXAMINATIONS [countable] BrE the mark you get in an examination: When do we get our exam results?

4 SUCCESS results [plural] things that happen successfully because of your efforts: get results (=succeed in getting what you want): If the program doesn't get results, it should be dropped.

result v to happen or exist as a result of sth [+ from]: problems resulting from past errors | result in sth phrasal verb to make sth happen; cause: an accident that resulted in the death of two passengers

bill=‫ﺻﻮرﺗﺤﺴﺎب‬

unemployment= The situation of not being able to find a job

recession= ‫رﻛﻮد اﻗﺘﺼﺎدي‬

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KEY WORD REVIEW (Part I): Fill in the blanks in each of the following sentences using the correct form of the words from the list below. There are some more words than you will need. Some of the words could be used more than once. _____________________________________________________________________________________

essential function develop development produce product productive result source 1. The engine will not ……….. without oil. 2. Industrial activities ………..pollutants which are source of air pollutions. 3. It is ………..that you work hard for this exam. 4. Some occupational diseases ………..from physical causes. 5. Math is ……….. for a career in computers. 6. This region ……….. most of the country’s wheat. 7. Scientists have ……….. a drug against this disease. 8. The amount of farm ……….. was increased by new farming methods. 9. The ……….. of the heart is to send blood round the body. 10. Farmers were more ……….. this year; they produced more agricultural products. 11. The treatment is beginning to show ………... 12. She ……….. the disease at the age of 27. 13. Enzymes are ……….. according to DNA codes. 14. There are new ……….. of science every day. 15. Iran’s oil reserves are an important ……….. of income. 16. We have reached the latest ……….. in nuclear energy technology. 17. Fruits are good ……….. of important vitamins like A and C. 18. She works in the research and ……….. (R&D) department for a drug company. 19. More research is necessary for the ……….. of a cure for diseases like AIDS and cancer. 20. Ninety per cent of the road deaths ……… from injuries to the head. 21. Children ……….. into adults. 22. We can live without clothes, but food and drink are ………...

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KEY WORDS: Before reading the TEXT, look through the following key words, and then do the KEY WORDS REVIEW.

Part II expose v 1 SHOW to show sth that is usually covered: The wolf opened its mouth to expose a row of sharp white teeth. | expose sth to sth: Wounds that are exposed to the air heal more quickly.

2 TO STH DANGEROUS to put someone in a harmful situation, position etc, where they have no protection against sth dangerous: expose sb to sth: The report revealed that workers had been exposed to unacceptably high levels of radiation.

3 SEE/EXPERIENCE to learn about beliefs, ideas etc, especially by seeing things or having new experiences: expose sb to sth: Travel abroad exposes children to different languages and cultures.

exposure n TO DANGER [countable, uncountable] the state of being put into a situation that is harmful because you have no protection from sth that is dangerous [+ to]: Skin cancer can be caused by prolonged exposure to the sun. | Through TV, kids have regular exposure to violence.

present v 1 GIVE to give sth to someone, especially at a formal or official occasion: present sb with sth: David's manager presented him with the award for best sales in the region.

2 CAUSE STH TO HAPPEN to cause sth to

Epidemiology

happen or exist: Slippery floors in the work area present a hazard to employees. | present a problem/ difficulty: This equation should present no problems if you know some basic trigonometry.

3 SHOW to offer or show information about sth in a particular way: The movie presents its characters in a way that I find difficult to believe in. | Tobacco companies are trying to present a more favorable image.

4 A SPEECH to give a speech in which you offer an idea, plan etc to be considered or accepted: present sth to sb: The team is presenting its report to the board on Tuesday.

presence n 1 [uncountable] the state of being present in a particular place: Your presence is requested at the club meeting on Friday. | [+ of]: The police scientists detected the presence of poison in the dead woman's blood.

—opposite absence (Unit1) 2 in sb's presence with someone or in the same place as them: John never seemed at ease in my presence. | The police will only interview a child in the presence of an adult.

express v 1 IN WORDS to tell people what you are feeling or thinking by using words: Bill's never been afraid to express his opinions. express sympathy/fear/anger etc: Parents have expressed their concerns about their children's safety. | express interest (=say that you are interested in sth): The public are expressing an increasing interest in green issues. | express opposition to (=say publicly that you do not agree with sth): Managers and

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players alike expressed opposition to the scheme. | express yourself (=let people know your thoughts and feelings so that they can understand): Young children often have difficulty expressing themselves. | can't express: Words can't express how angry we felt.

2 IN BEHAVIOUR/LOOK to let people know what you are feeling or thinking by the look on your face or by your behaviour: The look on Paul's face expressed his total contempt for them.

3 FEELING if a feeling expresses itself it can be clearly seen and understood: Major Hall's frustration expressed itself in occasional bouts of rage.

frustration= ،‫ﺳﺮﺧﻮردﮔﻲ‬ ،‫ﻧﺎﻛﺎﻣﻲ‬

transmit v transmitted, transmitting 1 to send out electric signals, messages etc by radio or other similar equipment; broadcast: The US Open will be transmitted live via satellite.

2 to send or pass something from one person, place or thing to another: an infection transmitted by mosquitoes

transmission n 1 [uncountable] the process of sending out of electrical signals, messages etc, by radio or similar equipment: We apologize for the break in transmission earlier in the programme.

2 [countable] formal sth that is broadcast on television, radio etc 3 [uncountable] formal the process of sending or passing of sth from one person, place, or thing to another: the transmission of disease

break=‫وﻗﻔﻪ‬

Epidemiology

association n [countable] 1 an organization that consists of a group of people who have the same aims, do the same kind of work etc: the Association of Master Builders | an association to help families suffering from alcoholism. 2 in association with made or done together with another person, organization etc: concerts sponsored by the Arts Council in association with several local businesses

direct v. 1. direct sth to/towards sb/sth; direct sth at sb/sth to point or send sth towards sb/sth or in a particular direction: In recent weeks the media’s attention has been directed towards events abroad. | Environmental policy was traditionally directed at pollution control. 2. to manage or control sb/sth: A policeman was in the middle of the road, directing the traffic. 3. direct sb (to…) to tell or show sb how to get somewhere: I was directed to an office at the end of the corridor.

directly adv 1 with no other person, action, process etc between: The new law won't directly affect us. | I know where you can get that directly from the manufacturers. 2 exactly: Have you noticed how he never looks directly at you? | Her practical ideas seemed directly opposed to the department's academic style. 3 speak/ask/answer etc directly to say exactly what

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you mean without trying to hide anything: Cindy has a job in mind, but refuses to say directly what it is.

KEY WORD REVIEW (Part II): Fill in the blanks in each of the following sentences using the correct form of the words from the list below. There are some more words than you will need. Some of the words could be used more than once. _____________________________________________________________________________________

association directly express expose exposure express present presence transmit transmission

1. The disease was ……….. by droplets in the air. 2. The whole class has been ……….. to the flu. 3. Lung cancer is………..related to smoking. 4. We work in ………..with our partner in other countries around the world. 5. Good teachers try to ……….. their materials in an interesting way. 6. Scientists done an experiment to test for the ……….. of oxygen. 7. A baby’s skin should not be ……….. to the sun for too long. 8. The ………..of malaria is done through mosquito bite. 9. ……….. to radiation is almost always harmful. 10. In recent weeks the media’s attention has been ………..towards at young people. 11. Vaccination is usually valuable only if it is given before a person is ……….. to disease.

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READING Control of Communicable and Certain Noninfectious Disease: Definitions

C

ertain terms with which one should be familiar are frequently used in the discussion of communicable and noninfectious diseases. Some common definitions are given here.

Disease: In its broadcast sense the communicable and noninfectious disease. Disease may be considered the antithesis of health, defined as "a state of physical, mental and social well-being and ability to function, and not merely the absence of illness or infirmity." 1 Communicable disease: An illness due to specific infections agent or its toxic product which arises through transmission of that agent or it products from a reservoir to a susceptible host, victor, or the inanimate environment. 2 Illness may be caused by bacteria, bacteria toxins, viruses, protozoa, spirochetes, parasitic worms (helminthes), poisonous plants and animals, chemical poisons, fungi, rickettsias, certain yeasts, and mold. In this text the communicable disease are grouped into respiratory disease, water- and foodborne disease, insectand rodentborne disease and zoonoses, and miscellaneous diseases. Noninfectious or non-communicable disease: The chronic and insidious diseases which develop usually over an extended period and whose cause may not be entirely clear. Cancer, alcoholism, blindness, mental illnesses, tooth decay, ulcers, and lead poisoning are regarded as disease (dis-ease). 3 Noninfectious disease would include cardiovascular diseases, nutritional deficiency diseases, carbon monoxide poisoning, and illness associated with toxic organic and 1

The WHO definition as modified by M. Terris, Approaches to an Epidemiology of Health,” Am. J. Pub. Health, October 1975, pp. 1037-1045. 2 Control of Communicable Diseases in Man, 12th ed., Am. Pub. Health Assoc., Washington, D.C., 1975. 3 From Prospectus-Manual on Prevention of Disease, Task Force on Prevention, Am. Pub. Health Assoc., Washington, D.C., 1976, p. 11.

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inorganic chemicals in air, water, and food. In contrast to the communicable disease, chronic diseases may be caused by a variety or combination of factors which is difficult to identify, treat and control. Carrier: An infected person (or animal) that harbors a specific infectious agent in the absence of discernible clinical disease and discernible serves as a potential source or infection for man. ‫ﻗﺎﺑﻞ‬ Contact: A person or animal that has been in such association with an infected person or animal or a contaminated environment as to have had opportunity to acquire the infection. Contamination: The presence of an infectious agent on a body surface; also on or in clothes, bedding, toys, surgical instruments or dressings, or other inanimate articles or substances including water, milk, and food. Pollution is distinct from contamination and implies the presence of offensive, but not necessarily infectious matter, in the environment. Disinfection: Killing of infectious agents outside the body by chemical or physical means, directly applied. Disinfestation: Any physical or chemical process serving to destroy or remove undesired small animal forms, particularly arthropods or rodents, present upon the person, the clothing, or in the environment of an individual, or on domestic animals. Endemic: The constant presence of a disease or infectious agent within a given geographic area; may also refer to the usual prevalence of a given disease within such area. Hyperendemic expresses a persistent intense transmission, e.g., malaria. Epidemic: The occurrence in a community or region of cases of an illness (or an outbreak) clearly in excess of normal expectancy and derived from a common or a propagated source.

‫ﺗﺸﺨﻴﺺ‬

Epidemiology

Transmission of Infectious Agents: Any mechanism by which a susceptible human host is exposed to an infectious agent. The mechanisms are 1. Direct Transmission: Direct and essentially immediate transfer of infectious agents (other than from an arthropod in which the organism has undergone essential multiplication or development) to a receptive portal of entry by which infection may take place. This may be by direct contact by touching, or by direct projection (droplet spread) of droplet spray onto the conjunctiva or onto the mucous membranes of the nose or mouth during sneezing, coughing, spitting, singing, or talking. 2. Indirect Transmission a. VEHICLEBORNE. Contaminated materials or objects such as toys, handkerchiefs, soiled clothing, bedding, surgical instruments, or dressing (indirect contact); water, food, milk, biological products including serum and plasma, or any substance serving as an intermediate means by which an infectious agent is transported and introduced into a susceptible host through a suitable portal of entry. b. VICTORBORNE i. Mechanical: includes simple mechanical carriage by a crawling or flying insect trough soiling of its feet or proboscis, or by passage of organisms through its gastrointestinal tract. ii. Biological: Propagation (multiplication) cyclic development, or a combination of these (cyclopropagation) is required before the arthropod can transmit the infective from of the agent to man. c. AIRBORNE: The dissemination of microbial aerosols with carriage to a suitable portal of entry usually the respiratory tract. Microbial aerosols are suspensions in air of particles consisting partially or wholly of microorganisms. i. Droplet nuclei: Usually the small residues from the evaporation of droplets emitted by an infected host. ii. Dust: the small particles of widely varying size witch may arise from contaminated floors, clothes, bedding, other articles; or from soil (usually fungus spores separated from dry soil by wind or mechanical stirring).

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Host: A man or other living animal, including birds and arthropods, affording under natural conditions subsistence or lodgment to an infection agent. Incubation period: The time interval between exposure to an infectious agent and appearance of the first sign or symptom of the disease in question. Reservoir of infectious agents: Any human beings, animals, arthropods, plants, soil, or inanimate matter in witch an infectious agent normally lives and multiplies and on witch it depends primarily for survival, reproducing itself in such manner that it can be transmitted to the susceptible host. Source of infection: the person, animal, object, or substance from witch an infectious agent passes immediately to a host. Susceptible: A person or animal presumably not possessing resistance against a particular pathogenic agent and for that reason liable to contract a disease if or when exposed to the disease agent. Carcinogen: Any factor or combination of factors witch increases the risk or cancer in humans. Epidemiology: The study of the occurrence, frequency, and distribution of disease in human populations, leading to the discovery of the cause and an informed basis for preventive action-social, biological, chemical, or physical.

Comprehension Check A. Answer the following questions. 1- What would be the best definition for non communicable diseases? 2- What does carrier mean? 3- How can one prevent indirect transmission? 4- When does an epidemic take place?

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B. TRUE OR FALSE: Put T for true and F for false statements. 1…… Illness may be caused by protozoa or bacteria. 2……Based on this text, the noninfectious diseases are divided into four groups. 3……Mental illnesses is an example of noninfectious diseases. 4…, Chronic diseases is a synonym for communicable illnesses. 5…… Killing of infectious agents outside the body is named disinfestation. 6…… The time interval between exposure to an agent and appearance of the first sign of the disease is called incubation period.

C. Choose the best choice to complete the sentences. 1- Cancer, blindness and tooth decay are examples of: a) noninfectious diseases c) communicable diseases

b) diseases (dis-ease) d) water-born diseases

2- In contrast to the communicable diseases, chronic diseases may be caused by: a) chemical poisons c) zoonoses

b) poisonous plants d) variety of combination of factors

3- Killing of infectious agents outside the body by chemical, directly applied is called: a) disinfection c) contamination

b) disinfestation d) transmission

4- Transmission through contaminated materials or objects defined as: a) vehicle born c) vector born

b) indirect contact d) agent transmission

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FURTHER READING

Diphtheria Diphtheria is an acute, toxin-mediated disease caused by the bacterium Corynebacterium diphtheriae. The name of the disease is derived from the Greek diphthera, meaning leather hide. The bacterium was first observed by Klebs in 1883 and cultivated by Löffler in 1884. Incubation Period: The incubation period of diphtheria is 2–5 days (range, 1–10 days). Occurrence: Diphtheria occurs worldwide, but clinical cases are more prevalent in temperate zones. Death: The overall case-fatality rate for diphtheria is 5%– 10%, with higher death rates (up to 20%) among persons younger than 5 and older than 40 years of age. The casefatality rate for diphtheria has changed very little during the last 50 years. Reservoir: Human carriers are the reservoir for C. diphtheriae and are usually asymptomatic. In outbreaks, high percentages of children are found to be transient carriers. Transmission: Transmission is most often person-toperson spread from the respiratory tract. Rarely, transmission may occur from skin lesions or articles soiled with discharges from lesions of infected persons (fomites). Temporal Pattern: In temperate areas, diphtheria most frequently occurs during winter and spring. Communicability: Transmission may occur as long as virulent bacilli are present in discharges and lesions. The time is variable, but organisms usually persist 2 weeks or less, and seldom more than 4 weeks, without antibiotics. Chronic carriers may shed organisms for 6 months or more. Effective antibiotic therapy promptly terminates shedding. Secular Trends: Diphtheria was once a major cause of morbidity and mortality among children. In England and Wales during the 1930s, diphtheria was among the top three causes of death for children younger than 15 years of age. Diphtheria continues to occur in other parts of the

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world. A major epidemic of diphtheria occurred in countries of the former Soviet Union beginning in 1990. By 1994, the epidemic had affected all 15 Newly Independent States (NIS). More than 157,000 cases and more than 5,000 deaths were reported. In the 6 years from 1990 through 1995, the NIS accounted for more than 90% of all diphtheria cases reported to the World Health Organization from the entire world. In some NIS countries, up to 80% of the epidemic diphtheria cases have been among adults. The outbreak and the age distribution of cases are believed to be due to several factors, including a lack of routine immunization of adults in these countries. Vaccination Schedule and Use DTaP (diphtheria and tetanus toxoids and a cellular pertussis vaccine) is the vaccine of choice for children 6 weeks through 6 years of age. The usual schedule is a primary series of 4 doses at 2,4,6, and 15–18 months of age. The first, second, and third doses of DTaP should be separated by a minimum of 4 weeks. The fourth dose should follow the third dose by no less than 6 months, and should not be administered before 12 months of age.

A. Vocabulary Drills I. Find single words in the text which match the following definitions. 1. of a time before now: 2. quickly; not late: 3. first; most important: 4. your usual way of doing things: 5. happening in the whole world: 6. most common in a particular place at a particular time: 7. no signs of the illness: 8. a general change or development: 9. not often: 10. becoming dangerous very quickly:

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II. Find words in the text which have the same meaning as: 11. cases connected with a hospital or clinic : 12. the period between becoming infected with a disease and showing the first physical signs of it: 13. parts of the world that is never very hot or very cold: 14. cause or because of sth or sb:

B. Comprehension Check 1. TRUE OR FALSE: 1…….. Diphtheria is a chronic disease caused by a bacterium. 2 ……..The bacterium was observed by Loffler in 1884. 3…….Transmission most often occur from skin lesions. 4……. The incubation period of diphtheria is 5-15 days. 5……. In England and Wales during the 1930s, diphtheria was the first caused of death. 6……. DTaP is the vaccine for children under 6 years of ages.

CLOZE PASSAGE Fill in the blanks with the appropriate words from the list below. Each word could be used more than once. active

causes prevent

dangerous examined leading permanently protected saved trained transmitted

Malaria Malaria is a serious disease spread through mosquito bites. Each year, there are 300 million to 500 million cases of malaria throughout the world and about 1 million child deaths. In areas where malaria is common, it can be the …………. cause of death and poor growth among young children.

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Malaria is also particularly dangerous for pregnant women. It …………. severe anaemia, miscarriages, stillbirths, low birthweight and maternal death. Many lives can be …… by the prevention and early treatment of malaria. What every family and community has a right to know about Malaria 1. Malaria is …………. through mosquito bites. Sleeping under a mosquito net treated with a recommended insecticide is the best way to ……………mosquito bites. 2. Wherever malaria is common, children are in danger. A child with a fever should be …………. immediately by a trained health worker and receive an appropriate antimalarial treatment as soon as possible. 3. Malaria is very …………. for pregnant women. Wherever malaria is common, pregnant women should …………. malaria by taking antimalarial tablets recommended by a health worker. 4. A child suffering or recovering from malaria needs plenty of liquids and food. 5. Families and communities can prevent malaria by taking action to stop mosquitoes from breeding. Supporting Information Malaria All members of the community should be …………. against, particularly young children and pregnant women, and especially between mosquito bites sunset and sunrise when mosquitoes are most ………….. Mosquito nets, curtains or mats that are dipped in a recommended insecticide …………. mosquitoes that land on them. Special, …………. treated mats should be used, or nets, curtains or mats that are dipped in insecticide regularly. Usually, the nets need to be re-treated when the rains begin, at least every six months, and after every third wash. …………. health workers can advise on safe insecticides and re-treatment schedules. Babies and other small children should sleep under a treated mosquito net. If the nets are expensive, the family should buy at least one big net, which the small children can sleep under. should sleep with their mothers under a net.

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Treated mosquito nets should be used throughout the year, even during times when there are fewer mosquitoes. If mosquito nets cannot be used, other actions can help: D curtains, cloths or mats impregnated with a recommended insecticide can be hung over doors and windows D screens can be put on doors and windows D mosquito coils or other fumigants can be used D clothing that covers the arms and legs (long sleeves and long pants or skirts) can be worn as soon as it begins to get dark. This is especially important for children and pregnant women. Malaria should be suspected if anyone in the family has a fever, or if young children refuse to eat or have vomiting, drowsiness or fits.

TRANSLATION ACTIVITY: I. Translate the following words or terms into Persian. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

host dust host vector carrier contact droplet rodents spitting endemic epidemic

12. reservoir 13. zoonoses 14. dressings 15. pollution 16. sneezing 17. outbreak 18. morbidity 19. mortality 20. coughing 21. arthropods 22. alcoholism

23. susceptible 24. disinfection 25. occurrence 26. epidemiology 27. disinfestation 28. hyperendemic 29. contamination 30. communicability 31. cyclopropagation

II. Translate the following phrases into Persian. 1. 2. 3. 4. 5. 6. 7. 8. 9.

mosquito nets mosquito mats portal of entry droplet spread droplet spray toxic product chronic carriers mosquito bites mosquito curtains

36. 37. 38. 39. 40. 41. 42. 43. 44.

respiratory disease waterborne diseases. foodborne disease insectborne disease rodentborne disease noninfectious diseases inanimate environment cardiovascular diseases surgical instruments

Epidemiology 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35.

safe insecticides breastfed babies antimalarial tablets direct transmission indirect transmission infections agent chemical poisons chronic diseases insidious diseases mental illnesses chronic diseases tooth decay lead poisoning soiled clothing infected host droplet nuclei susceptible host mechanical stirring incubation period human populations preventive action incubation period temperate zones case-fatality rate human carriers poisonous plants

45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70.

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domestic animals contaminated objects biological products mechanical carriage vehicleborne transmission communicable diseases airborne transmission microbial aerosols routine immunization source of infection occurrence of disease frequency of disease distribution of disease leading cause of death toxin-mediated disease toxic organic chemicals susceptible human host toxic inorganic chemicals non-communicable disease nutritional deficiency diseases carbon monoxide poisoning transmission of infectious agents contaminated materials or objects propagation cyclic development reservoir of infectious agents person-to-person transmission

III. Translate the following sentences into Persian. 1. Wherever malaria is common, children are in danger. 2. Malaria is a serious disease spread through mosquito bites. 3. The incubation period of diphtheria is 2–5 days (range, 1–10 days). 4. In temperate areas, diphtheria most frequently occurs during winter and spring. 5. Babies and other small children should sleep under a treated mosquito net. 6. Diphtheria occurs worldwide, but clinical cases are more prevalent in temperate zones. 7. The case-fatality rate for diphtheria has changed very little during the last 50 years.

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8. In England and Wales during the 1930s, diphtheria was among the top three causes of death for children younger than 15 years of age. 9. In areas where malaria is common, it can be the leading cause of death and poor growth among young children. 10. Carrier: An infected person (or animal) that harbors a specific infectious agent in the absence of discernible clinical disease and serves as a potential source or infection for man. 11. Malaria is very dangerous for pregnant women. Wherever malaria is common, pregnant women should prevent malaria by taking antimalarial tablets recommended by a health worker. 12. Noninfectious disease would include cardiovascular diseases, nutritional deficiency diseases, carbon monoxide poisoning, and illness associated with toxic organic and inorganic chemicals in air, water, and food. 13. illness may be caused by bacteria, bacteria toxins, viruses, protozoa, spirochetes, parasitic worms (helminthes), poisonous plants and animals, chemical poisons, fungi, rickettsias, certain yeasts, and mold. 14. Epidemiology: The study of the occurrence, frequency, and distribution of disease in human populations, leading to the discovery of the cause and an informed basis for preventive action-social, biological, chemical, or physical. 16. Indirect Transmission

a. VEHICLEBORNE. Contaminated materials or objects such as toys, handkerchiefs, soiled clothing, bedding, surgical instruments, or dressing (indirect contact); water, food, milk, biological products including serum and plasma, or any substance serving as an intermediate means by which an infectious agent is transported and introduced into a susceptible host through a suitable portal of entry. b. VICTORBORNE i. Mechanical: includes simple mechanical carriage by a crawling or flying insect trough soiling of its feet or proboscis, or by passage of organisms through its gastrointestinal tract. ii. Biological: Propagation (multiplication) cyclic development, or a combination of these (cyclopropagation) is required before the arthropod can transmit the infective from of the agent to man.