As the world grapples with the ongoing Covid-19 pandemic that originated in China, another health threat has emerged in East China’s Jiangsu and Anhui provinces. Deaths and infections have been reported due to Severe Fever with Thrombocytopenia Syndrome (SFTS), raising concerns about this new health threat.
Understanding SFTS
SFTS is caused by the Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV), which belongs to the Bunyavirus family. This virus gets transmitted to humans primarily through tick bites, especially from the Asian Longhorned Tick (Haemaphysalis longicornis). Humans can also contract the disease through regular contact with animals like goats, cattle, deer, and sheep. Despite being carriers of the virus, animals generally do not exhibit any symptoms associated with SFTSV. Farmers, hunters, and pet owners are particularly vulnerable due to their frequent interaction with these animals.
Origin and Spread of the Disease
The virus was first identified in China over a decade ago, with the initial cases reported in rural areas of Hubei and Henan provinces in 2009. Researchers identified the virus by examining blood samples from a group of people showing similar symptoms. It swiftly spread to other East Asian countries including Japan and South Korea, resulting in a significant increase in the total number of cases. Greater awareness regarding tick bites and associated health risks has led to a decrease in the fatality rate of the infection.
Incubation Period and Symptoms of SFTS
For SFTS, the incubation period, i.e., the interval between getting infected and displaying symptoms, varies from 7 to 13 days. The disease usually surfaces between March and November, peaking between April and July. People can experience various symptoms including fever, fatigue, chills, headache, nausea, muscle pain, diarrhea, vomiting, abdominal pain, gingival hemorrhage, and conjunctival congestion. Early warning signs include severe fever, low platelet count (thrombocytopenia), and a decrease in white blood cells (leukocytopenia). More severe cases may exhibit multi-organ failure, hemorrhagic manifestations, and symptoms associated with Central Nervous System (CNS) diseases.
Prevention and Treatment
Preventing SFTS involves avoiding tick-prone environments or wearing protective clothing in such areas. Usage of tick-repellent lotions and sprays on exposed body parts can also be beneficial. Regarding treatment, no vaccine is currently available for the disease. However, the antiviral drug Ribavirin has been found effective in treating the illness. This drug is also used to treat Crimean-Congo Haemorrhagic Fever (CCHF), another disease transmitted by ticks.
Current Case Fatality Rate and WHO Recognition
The fatality rate for SFTS currently stands between 16%-30%. Recognizing its fast-spreading nature and high fatality rate, the World Health Organisation (WHO) has listed SFTS among the top 10 priority diseases. This list identifies diseases and pathogens with potential to cause a public health emergency but lack effective treatments and vaccines. It includes Ebola, several other hemorrhagic fevers, Zika, Nipah, Middle East respiratory syndrome coronavirus (MERS-CoV), Severe Acute Respiratory Syndrome (SARS), and ‘disease X’, representing the need to prepare for an unknown pathogen causing a serious epidemic.