Question

How is prevalence affected in the following scenarios?

1. Strong improvement in treatment for those with HIV disease.

2. New strain of virulent TB that is resistant to antibiotics.

3. Increased maternal use of folic acid for reducing neural defects.

Answer 1

1. Antiretroviral drugs are treated to the patients in combination with other drugs,which is known as antiretroviral therapy(ART).It increases the life expectancy of patients and reduce the virus in blood and body fluids.In this way the prevalence of HIV can be affected.

2.Multi-drug therapy(MDT) or Extensive-drug therapy(XDT) should be applied to get rid off the new antibiotic resistant virulent TB strains.In this case the patient is treated with at least four drugs,like rifampin,over a period of six weeks. Use of second line drugs against which the strain is not resistant can be useful.

3.Folic acid supplementation can prevent 50% or more of the neural tube defects(NTD) such as spina bifida,anencephaly etc.During pregnancy,folic acid uptake is necessary for synthesis of tetrahydrofolate required in nucleotide,vitamin synthesis as well as correcting the NTD causing genetic defects.