As the water levels have started dipping in Kerala, doctors warn of an impending outbreak of diseases over the carcass, muck and filth left behind by the floods. This situation could also entail water-borne diseases and other epidemics, including communicable diseases that follow such natural disasters. It is time now to take up the challenging task of spreading awareness, getting rid of the waste, cleaning and prevent a major outbreak. Dr Dhruv Mamtora, Consultant Microbiologist and Infection control officer, S. L. Raheja Hospital, Mumbai, speaks about preparedness and priority interventions after floods.
Getting prepared for communicable disease outbreak
There are problems during natural disaster which include overcrowding, shortage of food & water supplies, lack of medical aid and sanitation. Even though the chances of epidemic are less likely, preparedness for the same is wiser than addressing issues later on. Broadly, there are chances of water-borne and vector-borne diseases.
Communicable water diseases could be caused by poor sanitation facilities and contaminated water sources which may occur due to overcrowding, open defecation and draining sewage of transient camps into water bodies from which the drinking water is obtained. There could be Vibrio cholerae, E.coli (toxigenic strain, Hepatitis A and Hepatitis E outbreaks.
Leptospirosis is a zoonotic disease which could be caused due to contamination of rodent urine in damp vegetation. It is well known disease that followed the Mumbai floods during 2000. It is also one of the monsoon-related illnesses.
Overcrowding could lead viral diseases like measles and acute respiratory illnesses, especially in non-vaccinated, under five children. Indoor cooking, lack of ventilation and poor nutrition are few of the 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 could 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 there are pockets for mosquito breeding which could 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 for preventing communicable diseases
Avoid sleeping outside or movement & transportation from mosquito prone areas; also avoid overcrowding and wear protective clothing to prevent mosquito bites. Massive construction activities following natural disaster could also lead to mosquito breeding. Hence, strict construction norms should be followed, especially with water storage tanks which could become sites for mosquito breeding.
Ensure safe and proper disposal of dead bodies following natural disasters which could act as a source of an outbreak.
Follow standard precautions, personal hygiene and wash hands with soap and water. Use properly chlorinated water, ensure food is cooked and solid waste is appropriately disposed
Medical facilities should make sure that medical waste gets discarded safely, early diagnosis and treatment for diseases is practiced and good surveillance systems of incidences report of newly occurring communicable diseases is ensured. Also maintain a checklist of stock of essential drugs, oral rehydraiton sachets, antibiotics and other important drugs required.
Reference: 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