Tuesday February 27, 2024

Flood and disease

September 10, 2022

Other than coping with the great losses of lives of loved ones and property, the survivors of the floods have to deal with several health issues as well; one of these looming risks is mosquito-borne infections. The apocalyptic floods have triggered historically significant outbreaks of mosquito-borne diseases in different areas of the world. Pakistan is no different, and we are already receiving reports about dengue and malaria outbreaks in the flood-affected areas.

One reason for this upsurge in mosquito-borne infections in the flood-affected areas is that the receding flood water can provide perfect conditions for mosquito breeding. Like all insects, mosquitoes flourish in warm conditions. Water is also critical for mosquitos’ life cycle, as they lay eggs in and around water. More water means more mosquitoes. With this increased breeding, the affected people are at great risk of being infected with life-threatening mosquito-borne diseases.

The dengue virus and plasmodium parasite (malaria-causing parasite) cause the most common mosquito-borne infections in Pakistan. On top of it, the coronavirus is still being pretty much here in Pakistan.

According to experts, after Covid-19, these are the five virus families that could cause the next pandemic: coronaviridae, flaviviridae, orthomyxoviridae, paramyxoviridae, and togaviridae (alphaviruses). The concern is that one of these families is the dengue virus family (flaviviridae). Other than dengue, the viruses of this family can cause several diseases including Japanese encephalitis, Zika, West Nile disease and others. Mosquito bites may spread the viruses of all these diseases when it comes to each virus.

The aedes mosquitoes that spread these viruses are widespread and routinely detected through surveillance in most areas of Pakistan. But some areas of the country are free of this species of mosquitoes. Another concern is that available research on rainfall has focused on changes in mosquito population distributions as the primary outcome rather than human disease incidence. The changes in mosquito population distributions can have adverse effects on human health, so we must take prompt measures in these areas to prevent the spread of mosquito-borne diseases.

Here are some personal protection measures that may lessen the risk of people getting bitten by mosquitoes. The first thing to do is to educate communities and provide essential personal protection items such as mosquito-repellent lotions, bed nets and full-sleeved clothing to the flood victims. The local administrations should organize massive cleanup drives as soon as the flood water recedes and lasts for weeks to come. There is not much one can do to stop mosquitoes from flying into neighbouring non-flooded areas, but insecticide spraying may provide some short-term protection.

The administration should try to draw people’s attention to repairing, replacing, or installing insect screens on windows and doors, as it can provide a physical barrier to mosquitoes seeking to fly inside their homes and offices. The municipal authorities shall pay special attention to regularly cleaning gutters, drains and water tanks that can be home to mosquitoes in flood-affected areas. The government should provide insecticide-treated clothing to military and paramilitary personnel who are taking part in rescue operations in flood-affected areas.

Climate change is expected to increase the frequency of flooding events as well as the spread of mosquito-borne diseases. So, what should we need to do in the long run for the health of the people who are already dealing with a sudden disaster? To get answers to these questions, the Institute of Public Health Lahore organized an international hybrid seminar on August 11 this year in collaboration with the Punjab government. International and local mosquito control experts discussed the diseases spread by mosquitoes in Pakistan and expressed their views on prevention of these diseases. The experts shed light on the relationship between climate change and mosquito-borne diseases, in particular and vector-borne diseases, in general.

The Q&A session of the seminar revealed that there we need public awareness campaigns. It was also concluded that perhaps a major reason for not understanding the depth of the problem is the lack of awareness. We need a large-scale health education campaign on this issue along with other routine activities. Because mosquito-borne diseases are community diseases, and prevention of these diseases is not possible without the participation of the community.

The bitter question is: are we ready to play our role in improving our health and our family’s instead of looking at the government? An even more bitter fact is that people are not willing to play their part until they are satisfied with the government's action.

The writer is an assistant professor at the Department of Medical Entomology and Parasitology, Institute of Public Health, Lahore. He can be reached at: