Question

How does paragraph 3 contribute to the development of ideas in the text?

A
It emphasizes the positive impact that vaccines have had on people’s overall health.
B
It shows how potentially dangerous some diseases can be to people.
C
It reveals that not everyone takes vaccines to protect against these diseases.
D
It stresses how some diseases continue to persist despite vaccines.

Answer 1

A. It emphasizes the positive impact that vaccines have had on people’s overall health

Explanation:

• The above extract is from the article What is Vaccine by Lindsey Konkel wherein the author describes what a vaccine is and how it affects the body.
• The author states vaccines are substances which prepare the immune system to fight any pathogen or disease-causing germ by imitating an infection.
• The author says that vaccines as helped eradicate completely  many diseases such as Smallpox. and polio too has considerably reduced. Outbreaks of diphtheria  and measles are rare, particularly in the US. Tetanus infections also continue to decline worldwide

Answer 2

• Vaccination has greatly reduced the burden of infectious diseases. Only clean water, also considered to be a basic human right, performs better. Paradoxically, a vociferous antivaccine lobby thrives today in spite of the undeniable success of vaccination programmes against formerly fearsome diseases that are now rare in developed countries.

• Understandably, vaccine safety gets more public attention than vaccination effectiveness, but independent experts and WHO have shown that vaccines are far safer than therapeutic medicines. Modern research has spurred the development of less reactogenic products, such as acellular pertussis vaccines and rabies vaccines produced in cell culture. Today, vaccines have an excellent safety record and most “vaccine scares” have been shown to be false alarms.Misguided safety concerns in some countries have led to a fall in vaccination coverage, causing the re-emergence of pertussis and measles.

• Putative vaccine safety issues are commonly reported while reviews of vaccine benefits are few. A Medline search over the past five years using the keywords “vaccine risks” scored approximately five times as many hits (2655 versus 557) as a Medline search using “vaccine benefits” as keywords. This reflects the fact that negative aspects of vaccination get much more publicity than positive aspects.

• How one addresses the antivaccine movement has been a problem since the time of Jenner. The best way in the long term is to refute wrong allegations at the earliest opportunity by providing scientifically valid data. This is easier said than done, because the adversary in this game plays according to rules that are not generally those of science. This issue will not be further addressed in this paper, which aims to show how vaccines are valuable to both individuals and societies, to present validated facts, and to help redress adverse perceptions. Without doubt, vaccines are among the most efficient tools for promoting individual and public health and deserve better press.

• Disease control benefits
• Eradication
• Unless an environmental reservoir exists, an eradicated pathogen cannot re-emerge, unless accidentally or malevolently reintroduced by humans, allowing vaccination or other preventive measures to be discontinued.

• While eradication may be an ideal goal for an immunization programme, to date only smallpox has been eradicated, allowing discontinuation of routine smallpox immunization globally. Potentially, other infectious diseases with no extrahuman reservoir can be eradicated provided an effective vaccine and specific diagnostic tests are available. Eradication requires high levels of population immunity in all regions of the world over a prolonged period with adequate surveillance in place.9 The next disease targeted for eradication is polio, which is still a global challenge.Although high coverage with oral polio vaccine (OPV) has eliminated type poliovirus globally, transmission of types 1 and 3 continues in limited areas in a few countries. OPV-caused paralytic disease, directly or by reversion to virulence, and persistent vaccine-virus excretion in immunodeficient individuals are problems yet to be solved. Global use of monovalent type 1 and type 3 OPV and inactivated polio vaccine (IPV) may eventually be required.

• Elimination
• Diseases can be eliminated locally without global eradication of the causative microorganism. In four of six WHO regions, substantial progress has been made in measles elimination; transmission no longer occurs indigenously and importation does not result in sustained spread of the virus. Key to this achievement is more than 95% population immunity through a two-dose vaccination regimen. Combined measles, mumps and rubella (MMR) vaccine could also eliminate and eventually eradicate rubella and mumps.Increasing measles immunization levels in Africa, where coverage averaged only 67% in 2004, is essential for eradication of this disease. Already, elimination of measles from the Americas, and of measles, mumps and rubella in Finland has been achieved, providing proof in principle of the feasibility of their ultimate global eradication. It may also be possible to eliminate Haemophilus influenzae type b (Hib) disease through well implemented national programmes, as experience in the West has shown.

• Local elimination does not remove the danger of reintroduction, such as in Botswana, polio-free since 1991, with importation of type 1 poliovirus from Nigeria in 2004, and in the United States of America (USA) with measles reintroduced to Indiana in 2005 by a traveller from Romania.

• For diseases with an environmental reservoir such as tetanus, or animal reservoirs such as Japanese encephalitis and rabies, eradication may not be possible, but global disease elimination is a feasible objective if vaccination of humans (and animals for rabies) is maintained at high levels.