Tomato flu

A letter by concerned specialists has warned of a new mystery virus impacting young children in India…

The virus, dubbed the ‘tomato flu’ thanks to the symptomatic eruption of red and painful blisters all over the body that can gradually enlarge to the size of a tomato, was first identified in the Kollam district of Kerala, India, on May 6 and has so far infected 82 children under the age of 5.

The outbreak was detected by EPIWATCH, a system which uses Al and open-source data to capture early detection signals for potential epidemics.

In addition to blisters, tomato flu appears to cause a mild illness that initially resembles COVID (fever, fatigue, and initial body aches), though further symptoms can include nausea, vomiting, diarrhoea, fever, dehydration, swelling of joints, continued body aches, and common influenza-like symptoms.

The correspondence, published August 17th in The Lancet Respiratory Medicine, suggested that the virus is spread by close physical contact, noting that young children are especially exposed through use of nappies, touching unclean surfaces, and placing objects directly into their mouths.

Co-author Professor Vasso Apostolopoulos, the Pro Vice-Chancellor and Immunology and Translational Group Leader at Victoria University, said that given the similarities to hand, foot, and mouth disease (HFMD), transmission might lead to serious consequences by spreading in adults as well.

“We are still trying to identify exactly what this virus is. Its symptoms are like dengue fever and Chikungunya virus, which are common in the area, but it doesn’t appear to be them. Similarly, it also shares symptoms with HFMD,” Professor Apostolopoulos said.

“At the moment it looks like the virus is mild and goes away on its own, but most people who have had this infection are young, and we don’t really know what might happen in an immunocompromised person or if it spreads to elderly people.

“There is a case study of two children returning to the UK from India, who had these symptoms and tested positive for enterovirus, which is one cause of HFMD.”

A letter to the editor of The Paediatric Infectious Disease Journal, published by the team of UK doctors who dealt with the children on August 19th, reported that a 13-month-old girl and her older 5-year brother had developed rashes on their hands and legs, one week after returning from a month-long family holiday to Kerala in May 2022, where they visited friends and relatives in various cities.[1]

“In this case, the enterovirus shared some sequences with a strain of virus called Coxsackie A16, but it is not entirely the same, although it appears it is probably from the clade of this virus,” Professor Apostopoulos said.

Phylogenetic analysis showed that the tomato flu partial CA16 sequences from Kerala shared a most common recent ancestor with a clade originating in China.

Professor Andreas Suhrbier, a Group Leader of Inflammation Biology at QIMR’s Berghofer Medical Research Institute, agreed that the tomato flu is likely a variety of HFMD caused by Coxsackievirus A16, and pointed out that the virus and existing forms of HFMD are common worldwide, including in Australia.

“The disease is generally mild, lasting 7-10 days, with symptoms including fever, rash, sometimes mouth sores, and joint pains,” Professor Suhrbier said.

“The virus can spread rapidly and can be transmitted on unwashed hands, surfaces contaminated by faeces, and via droplets from sneezing or coughing.”


[1] Tang, Julian W. BA, MA, MBChB, PhD, MRCP, FRCPath*,†; Iqbal, Aitka MD‡; Hamal, Shama MD*; Mohamedanif, Tarannum BSc*; Tipping, Leah F. MSc*; Toovey, Oliver T.R. MD*; Celma, Cristina C. PhD§; Beard, Stuart PhD§; Barer, Michael R. MD, PhD*,†. Kerala Tomato Flu – A Manifestation of Hand Foot and Mouth Disease. The Pediatric Infectious Disease Journal: August 19, 2022 – Volume – Issue – 10.1097/INF.0000000000003668 doi: 10.1097/INF.0000000000003668