Flooding in Kerala has left behind a huge wreckage and numerous people homeless. People had to take refuge wherever possible. More than 350 people died and 700,000 have been displaced. People from all over India are helping in some way or another by sending donations, clothes, food and offering place to stay. Even the foreign nations are coming to aid.
As the water levels have gone down, people are returning home just to see piles of mud, garbage and dead animals. The major challenge now is to get rid of all this, clean and prevent a major disease outbreak. These situations may easily give rise to water borne diseases and other epidemics. In the due course, it is important to spread awareness for prevention of communicable diseases which may follow such natural disaster. After all it is the efforts of community which will again restore Kerala.
Dr Dhruv Mamtora, Consultant Microbiologist and Infection control officer, S. L. Raheja Hospital, Mumbai, speaks about preparedness and priority interventions after floods.
Preparedness for communicable disease outbreak following disaster:
There are problems during natural disaster which include overcrowding, shortage of food and water supplies, lack of medical aid and sanitation issues. Even though chances of epidemic are less likely, preparedness for same is wiser than addressing same issues at later date.
Outbreak is sudden occurrence of diseases which is far more than the usual prevalence in that given area or geographic condition. Broadly there can be waterborne diseases, vector borne diseases and diseases which may be due to overcrowding.
Communicable water diseases may be due to poor sanitation facilities and contaminated water sources which may be in turn due to overcrowding, open air defecation and draining sewage of transient camps in water bodies from which the drinking water is obtained. There can be Vibrio cholerae, E. coli (toxigenic strain, Hepatitis A and Hepatitis E outbreaks.
Leptospirosis is a zoonotic disease which can be due to contamination with rodent urine and in damp vegetation. It is well known entity following Mumbai floods during 2000 and is one of diseases of monsoon related illness.
Overcrowding can lead to outbreak of viral diseases like measles and acute respiratory illnesses especially in non-vaccinated, under age 5 children. Indoor cooking, lack of ventilation and poor nutrition are few of precipitating factors for such diseases. Measles outbreak occurs in communities with low vaccination coverage and where herd immunity is low. Meningitis due to Neisseria meningitidis can be transmissible through personal contact and through respiratory route due to overcrowding.
Vector borne diseases are not related to immediate flooding which washes away breeding sites but few weeks following flood, there are pockets for mosquito breeding which can lead to malaria, dengue and other fever related illnesses. Malaria is related to fresh water collection during monsoon and dengue haemorrhagic fever is related to disruption of solid waste disposal services and water supplies which is not directly related to flooding.
Priority interventions following natural disaster for preventing communicable diseases
Avoid sleeping outside, movements and transportation from mosquito prone areas, avoid overcrowding and protective clothing to prevent mosquito bites are to be used. Massive construction activities following natural disaster can also lead to mosquito breeding and hence strict construction norms are to be followed and ensure that the water storage tanks do not become sites for mosquito breeding.
Ensure safe and proper disposal of dead bodies following natural disaster which can act as source for outbreaks.
Follow standard precautions, personal hygiene and wash hands with soap and water. Use properly chlorinated water, ensure cooked food and appropriate disposal of solid waste and sewage.
Medical facilities to ensure that medical waste discarded safely, and standard precautions and hand hygiene are followed. Ensure early diagnosis and treatment for diseases and good surveillance systems to report incidences of newly occurring communicable diseases. Ensure the stock of essential drugs, Oral rehydration sachets, antibiotics and other important drugs are available.
Government authorities to ensure that good hygiene, good food preparation, chlorination of drinking water, early treatment to sick patients and vector control measures are implemented.
Disaster preparedness plan should incorporate lessons from major disaster to agenda for future preparedness for same.
Watson JT, Gayer M, Connolly MA. Epidemics after Natural Disasters. Emerg Infect Dis. 2007;13(1):1. https://dx.doi.org/10.3201/eid1301.060779