The infection usually appears with fever, rashes or blisters on the skin and painful sores in the mouth.
The ongoing outbreaks of Hand Foot and Mouth Disease in many parts of the State are caused by Coxsackievirus A6 and Coxsackievirus A16, with both strains currently circulating in the State, according to virology profiling done at the Institute of Advanced Virology in the capital.
A common viral infection affecting young children, HFMD is not considered to be a major public health problem. However, the disease has suddenly become more prevalent than ever in Kerala and is reported in almost all districts, with adults also developing the infection occasionally.
“IAV is in the process of establishing its diagnostic laboratories and as part of surveillance studies, we have been collecting samples from hospitals in the periphery. Genomic sequencing studies done of HFMD samples from Thiruvananthapuram and Kollam districts, identified both Coxsackievirus A6 and A16, the former being the predominant strain,” the Director of IAV, E. Sreekumar, said.
Studies of HFMD done in the State in 2010-12 have reported Enterovirus 71 (EV-A71) to be the typical agent causing HFMD. However, a study done by the Dermatology Department of Government Medical College, Kozhikode in 2015-16 (study published in 2018) had also reported the co-circulation of both Coxsackievirus A6 and A16 to be the cause of HFMD in North Kerala.
Coxsackievirus A6 is said to cause more serious symptoms. While no correlating clinical data is forthcoming, there are reports that in many cases, lesions can be seen all over the body and not just hand and foot.
HFMD usually appears with fever, rashes or blisters on the skin and painful sores in the mouth. The infection, while mild, is very contagious and can spread through person-to-person contact and through aerosol transmission of respiratory droplets containing virus particles which are released when the infected person sneezes or coughs.
The fluid from the blisters can also transmit the disease.
With isolation and symptom management, the infection resolves within 7-10 days. Rare complications include brain infections or meningitis, but it is not clear if such instances have been reported in the State.
“HFMD, though mild, has become highly transmissible in the State in recent times and the outbreaks have become more widespread. Better surveillance and reporting is one reason. The other reason is the phenomenon of “immunity debt” among children. Children, after remaining unexposed to all bacteria and viruses during the two years of COVID, are suddenly experiencing a surge in common infections in the aftermath of school reopening,” says T. S.Anish, Additional Professor of Community Medicine, Govt Medical College, Manjeri.
All common infections, including viral fever, HFMD and respiratory infections have been high among school children this season because of the immunity debt concept in play, he points out.
Another natural epidemiological transition that is happening in all developing nations is that bacterial infections are all going down, to be replaced by viral infections. Better hygiene has reduced bacterial infections but the rise in viral infections cannot be prevented, Dr. Anish points out.