The 2017 dengue outbreak in Kerala was one of its worst ever. For a state which is often heralded as one with the best health indicators in the country, its numbers were shocking. With 37 deaths and nearly 20,000 reported cases, Kerala was one of the worst affected states in the country. Just as the state administration is preparing itself for the monsoon ahead, another challenge has presented itself: the state is now worried about high-risk ‘second attacks’.
Preliminary analysis of the data collected for an ongoing study by the World Health Organisation (WHO) and the Government of Kerala has found that 42% of the children between 9-12 age group in Thiruvananthapuram have already tested positive for dengue, at least once, reports TNIE. This indicates that a high population of children in Kerala have already been diagnosed once. Health administrators say that the additional challenge now, therefore, is of ‘second attack’ which could lead to ‘severe dengue’, which could be more fatal than dengue.
Several strains of dengue
There is dengue, and there is severe dengue. When the dengue virus progresses into a more serious condition – with symptoms like bleeding under the skin, frequent vomiting and abdominal pain – it can become ‘dengue hemorrhagic fever’, simply known as severe dengue. This can be fatal.
As the WHO factsheet on dengue explains, there are 4 distinct, but closely related, strains of the dengue virus, each called a ‘serotype’. “Recovery from infection by one provides lifelong immunity against that particular serotype,” the factsheet explains, however, “Subsequent infections by other serotypes increase the risk of developing severe dengue,” WHO says.
Dr PS Indu, Head of the Department of Community Medicine at Thiruvananthapuram Medical College Hospital explains it further, “If a child is infected with one serotype and recovers, there will be immunity against that particular serotype in the future. However because of the multiple serotypes, if the same child happens to be infected with another serotype, then there are high chances of child falling sick with severe dengue.”
And this is precisely the fear that Kerala is now battling. An officer with the health department told TNIE, “This time, we are expecting fewer number of affected cases and a marginal increase in the death rate.”
What is being done?
There is no specific treatment for dengue or severe dengue, which is why the focus of health administrators has been on prevention. In fact, early detection and access to proper medical care can lower fatality rates to below 1%. And the best way to prevent the diseases is by controlling the breeding of carriers – or ‘vectors’ – of the disease, mosquitoes.
The Kerala government is focusing on creating awareness. When asked about the preparedness of the government to face a possible dengue crisis in the upcoming monsoon season, Dr Sarita RL, Director of Health Services, told TNM that the various programmes done under Arogya Jagratha Project are being implemented to avert the crisis. She stressed that this year, with all the activities done so far to generate awareness and promote preventive measures, it is highly unlikely for a dengue epidemic to occur.
Officials say that the WHO study itself is a step towards understanding how dengue can be prevented in the state.
Rajeev Sadanandan, Additional Chief Secretary, Department of Health & Family Welfare, Government of Kerala says, “We have been having dengue infection since 1998 and we have not been able to control it. We are looking at different aspects of it through this study. One is the vector, then the management of cases, the study of complications of managing dengue - which we will be doing this year also. All these past years we are trying to do the same thing and hoping for a difference, whereas this study will help us identify the possibility or rather the need for vaccination. And also to look at alternate strategies for managing the vector.”
“The recent discussions we had with the WHO team were on how do we use some international best practices on vector management. We are also studying the prevalence to see the need for any revision of strategies,” Rajeev adds.
Dr Indu adds, “The remaining part of the study will be done among patients who have dengue fever. We would follow them up and measure their complications. We would also look at the factors, like predictors and determinants. With this study, we will be able to identify the factors which can predict a good or bad outcome.”