Even as Influenza A (H1N1) spreads unabated in the community in Kerala, a shift in the pattern of the epidemic seems evident, with the epicentre of the infection now shifting to the northern districts.
Public health experts say the current wave of the infection is almost past its peak in Thiruvananthapuram and Kollam and the number of cases will start dwindling in about two weeks in these southern districts.
More number of cases is now being confirmed in northern districts, indicating the shift. Nearly 70 per cent of the throat swabs sent to the labs these days have tested positive, indicating that the virus is widespread.
“We are testing only a fraction of cases because testing is a resource-intensive activity and in an epidemic situation, the numbers do not really matter. Hundreds are being infected by the virus daily, but much of it resolves spontaneously. The shift in pattern will indicate that almost all of the population down south has been affected by the virus,” a public health expert says.
Surveillance study
A surveillance study of blood samples in a random sample of the population will determine the level of sero prevalence of antibodies against the virus in the community. In short, a sero surveillance study will indicate the level of immunity against the virus in the community.
This information can be crucial as it will indicate if another spell of the infection should be expected. The level of sero prevalence of immunity will also prove crucial for the State in deciding its future strategies, such as vaccinating pregnant women and children against the infection, experts say.
In fact, a sero surveillance study was suggested by an expert team which had come to the State to do an epidemiological investigation, Health Department sources say.
Kerala has requested the Union Health Ministry to provide an imported vaccine (Sanafu) for one lakh pregnant women in the State as the high mortality among this section from the infection during its second spell has been a cause for concern. The State had received a first instalment of 45,500 doses of the vaccine and an additional stock of 30,000 doses for vaccinating health professionals.
However, some public health professionals feel that Kerala, with approximately 5.5-lakh live births a year, should have pressured the Centre to revise the vaccine policy for the State.
Ever since the beginning of the outbreak, vulnerability of pregnant women to the infection has been clearly established.
