China was the source of several virus infections like SARS (Severe Acute Respiratory Syndrome), H5N1, and H7N9 bird flu that caused widespread illness and death all over the world in the recent past. These include SARS-CoV-2 (the virus responsible for COVID-19), virus first detected in Wuhan, China in December 2019 which spread rapidly infecting millions of people around the world.
Some of the high-profile viral diseases that originated in China include:
1. Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)
Symptoms: Fever, chills, cough, shortness of breath, and in severe cases, pneumonia and respiratory failure.
Origin: The first recognized cases of SARS were reported in November 2002 in Guangdong province of China. It was initially spread by a healthcare worker who had travelled to Hong Kong in February 2003, where the virus then spread rapidly, resulting in a major outbreak. The virus is believed to have originated from bats which are known to have the ability to host many types of viruses without showing any symptoms, while civet cats (a type of mammal) sold at wet markets in China becoming infected with the virus after eating bat droppings or bat-infected animals and further transmitted the virus from bats to humans. Soon the virus spread to several countries, causing a global outbreak.
Impact: The outbreak of SARS spread quickly between late 2002 and 2003 resulting in widespread illness and death in many countries in Asia, North America, Europe, and Canada. The disease spread to 29 countries causing widespread global health concern. About 20% of SARS patients developed severe pneumonia, leading to acute respiratory distress syndrome (ARDS), which required mechanical ventilation and intensive care treatment. Fatalities occurred mainly in patients who were elderly or had pre-existing health conditions. Major outbreaks were reported in China, Hong Kong, Taiwan, Canada, Singapore, and other countries in Southeast Asia. Although SARS was contained relatively quickly, it demonstrated how rapidly viruses could spread in a highly interconnected world.
2. H7N9 Avian Influenza (Bird Flu)
Symptoms: Fever, cough, Sore throat, muscle ache, fatigue and shortness of breath leading to acute respiratory distress syndrome (ARDS), pneumonia, multi-organ failure and death. The severity of the infection largely depends on the individual’s health status, age, and timely medical intervention. The incubation period is typically between 2 to 8 days, though symptoms can sometimes appear as early as 1 day or as late as 10 days after exposure. Many individuals infected with H7N9 need ventilators and intensive care due to severe respiratory failure, creating a significant strain on already overburdened healthcare facilities. Vulnerable populations include the people with chronic illnesses (e.g., diabetes, hypertension, and heart disease), elderly people and individuals with weakened immune systems. Such people are more likely to experience severe outcomes from the infection.
Origin: The H7N9 strain of avian influenza first detected in China in 2013 primarily spread from infected poultry (domestic chickens, ducks and turkeys) to humans. The virus gained global attention because of its potential to cause severe disease in humans, with significant fatality rates in those infected. The initial outbreak was concentrated in China, particularly in eastern and southern regions, but spread to other parts of Asia and even beyond, leading to international concern. Outbreaks have continued intermittently in various parts of the world, including Taiwan, Hong Kong, and Macau.
Impact: The outbreak led to over 1,500 human infections and around 600 deaths. A majority of cases have been reported in China, with occasional cases in Taiwan, Hong Kong, and other neighbouring counties. Despite efforts to control it, sporadic cases have continued to occur, and the virus remains a concern due to its potential to mutate and cause a pandemic. The Chinese government had to spend millions to control outbreaks and prevent further spread of the virus.
Also Read: What is HMPV virus tormenting China? How serious is its threat and can it be prevented?
3. Coronavirus Disease 2019 (COVID-19)
Symptoms: Fever, dry cough, fatigue, loss of taste or smell, difficulty breathing, and in severe cases, pneumonia, acute respiratory distress syndrome, and organ failure. In more severe cases, the infection can progress to pneumonia, acute respiratory distress syndrome (ARDS), multi-organ failure, and sepsis, particularly in older adults and individuals with underlying health conditions such as cardiovascular disease, diabetes, and immunocompromised states. Some individuals may require mechanical ventilation, intensive care, or even ECMO (extracorporeal membrane oxygenation), a machine that helps oxygenate the blood. Some individuals experience a condition often referred to as long COVID that persist long after the acute phase of infection has passed. This can include fatigue, shortness of breath, difficulty concentrating (often called “brain fog”), joint pain, and more. The incubation period for COVID-19 is about 4-14 days. In most cases symptoms appear within 5-6 days of exposure though some asymptomatic individuals can also carry and spread the virus, making its control more challenging.
Origin: COVID-19 an infectious disease caused by the SARS-CoV-2 virus, was first identified in Wuhan the capital of Hubei province of China where live animals were sold for food, in December 2019 and quickly became a global pandemic. SARS-CoV-2 is thought to have originated from bats, with an intermediate host, possibly a pangolin, facilitating transmission to humans in a wet market in Wuhan. World Health Organization (WHO) declared COVID-19 a global pandemic on March 11, 2020, after the virus spread across countries and continents, overwhelming health systems, disrupting economies, and altering daily life globally.
Impact: The COVID-19 pandemic has had a profound impact globally, infecting over 760 million people and causing more than 6.8 million deaths (as of early 2025) in nearly every country in the world particularly the United States, India, Brazil, and Russia which were among the hardest-hit countries in terms of confirmed cases and deaths. It triggered worldwide lockdowns, overwhelmed healthcare systems, and led to widespread economic and social disruption. Global GDP shrank by over 3% in 2020. Many people lost their jobs, and unemployment rates surged. It remains a major global health issue.
4. H5N1 Influenza Virus
Symptoms: Fever, cough, sore throat, muscle aches, fatigue, shortness of breath and difficulty breathing, chest pain, diarrhoea (in some cases), conjunctivitis (eye infection) as well as pneumonia, sepsis, ARDS (acute respiratory distress syndrome), multi-organ failure (such as liver or kidney failure) and death in severe cases.
Origin: H5N1 is primarily an avian virus. It is found in respiratory droplets and faeces of infected birds and domestic poultry. The H5N1 virus causes severe illness and high mortality rates in domestic poultry, including chickens, ducks, and turkeys. The migratory birds spread the virus over long distances. The humans get the infection when they come in contact with the infected birds, their droppings, or feathers in live bird markets.
Impact: Although it has not caused a global pandemic, H5N1 remains a concern because of its high mortality rate in humans typically between 50% and 60%, making it one of the most lethal strains of influenza in human history.
5. Zika Virus
Symptoms: Fever, rash, joint pain, and conjunctivitis (red eyes). Zika virus is generally mild in adults but can cause significant complications in pregnant women and their babies. It is most dangerous in pregnant women, and can cause microcephaly (small head size) as well as other birth defects and neurological disorders in new-born babies.
Origin: The Zika virus is primarily transmitted by Aedes mosquitoes. The first case of Zika virus was reported in 2016 in Guangdong Province located in the southern part of China. Since most of the cases of Zika virus were detected in Guangdong, Hainan, Yunnan and Fujian provinces which are more prone to Zika outbreaks due to the presence of Aedes mosquitoes, particularly the Aedes aegypti species, which is the primary vector for Zika. These areas have a warm, humid climate, which is conducive to the breeding of these mosquitoes.
Impact: While Zika virus is not considered a major endemic disease in China, sporadic cases have been reported, particularly in the southern regions of the country that are more conducive to the mosquitoes that spread the virus. China, like many other countries, has participated in global efforts to research and develop a Zika vaccine. Several Chinese institutions have been involved in clinical trials for Zika virus vaccines, though no specific vaccine is currently licensed for use in China.
6. Langya virus
Symptoms: The symptoms of Langya virus infection may include persistent fever for several days, fatigue, dry cough, dizziness, muscle pain, headache, nausea, vomiting, discomfort or pain in the abdominal region, leukopenia or decrease in the number of white blood cells, liver and kidney dysfunction. In some severe cases it might lead to liver damage or elevated liver enzymes (transaminases), mild kidney dysfunction, and respiratory problems. The incubation period for Langya virus infection is still under investigation but is believed to range from 1 to 2 weeks after exposure to infected animals or their secretions.
Origin: Langya virus, also known as LayV a type of henipavirus was first reported in a study published in the New England Journal of Medicine in August 2022. The primary reservoir for the virus is believed to be shrews- a small, insectivorous mammal, particularly the Chinese mole shrew (Crocidura species), which was found to carry the virus in high amounts. Langya virus is thought to be transmitted through body fluids including saliva, urine, or faeces of shrews.
Impact: The virus was first detected in the Shandong and Henan provinces of China and caused significant concern due to its potential to spread and cause severe illness. As of now, there are no specific treatment or vaccines for Langya virus and its potential for causing severe disease or widespread outbreaks is still being studied. Management is symptomatic, focusing on relieving symptoms and addressing any complications (e.g., supportive care for liver and kidney issues). Antiviral drugs have been used in some cases, but their efficacy against Langya virus is not yet well established.
7. Human metapneumovirus (HMPV)
Symptoms: HMPV is a respiratory virus that belongs to the Metapneumovirus genus within the Paramyxoviridae family. It causes respiratory infections, particularly in young children, the elderly, and individuals with weakened immune systems. It can lead to a range of symptoms like fever, cough, runny nose, sore throat, and fatigue. In severe cases, particularly in young children, elderly adults, or those with weakened immune systems, HMPV can cause more severe infections, like wheezing, shortness of breath, difficulty breathing, pneumonia and bronchiolitis (inflammation of the small airways in the lungs) leading to hospitalization. The incubation period for HMPV is generally 3 to 6 days after exposure. For mild infections, treatment typically involves hydration, fever control, and rest. In severe cases, particularly with pneumonia or bronchiolitis, oxygen therapy may be necessary to help patients breathe more easily. Severe cases, especially infants, elderly, or immunocompromised individuals, may require hospitalization for intravenous fluids, oxygen, and more intensive care.
Origin: HMPV was identified in 2001 by researchers from the Erasmus Medical Center in Netherlands. The virus was found to share some genetic features with respiratory syncytial virus (RSV), but distinct enough to warrant its classification as a new virus. The virus was named Human Metapneumovirus (HMPV) based on its genetic relationship to pneumoviruses, a genus of viruses within the Paramyxoviridae family, which also includes RSV. The prefix “Meta” reflects its similarity to metapneumoviruses, which are closely related but have distinct characteristics.
Impact: HMPV is often underdiagnosed, especially because of overlaping symptoms with other respiratory viruses like RSV and influenza which can result in misdiagnosis or a lack of targeted treatments. In some cases of HMPV is mistaken for common colds, influenza, or RSV infections, delaying accurate treatment. The clinical presentation of HMPV, such as fever, cough, wheezing, and shortness of breath, is similar to other respiratory viruses. This makes it challenging to differentiate between HMPV and other viruses, particularly in high-risk populations. The biggest problem is that Human Metapneumovirus (HMPV) does not have a specific antiviral treatment or vaccine as of now and its treatment primarily focuses on supportive care to manage the symptoms and help the body recover.
8. Middle East Respiratory Syndrome (MERS)
Symptoms: Fever, cough, shortness of breath, and in severe cases, pneumonia, kidney failure, and death.
Origin: The first confirmed case of MERS in China occurred in May 2015 when a 32-year-old male who had travelled to South Korea and Saudi Arabia was diagnosed with MERS upon returning to Guangdong Province in southern China. Since then, China has reported cases of MERS, usually among travellers returning from the Middle East, South Korea, or other regions. Camels have been identified as the primary animal host for MERS-CoV in the Middle East. Chinese travelers and workers who visit camel farms in these regions are advised to avoid handling camels or consuming raw camel milk.
Impact: MERS has caused several hundred cases globally, with a high fatality rate (around 35%). While it hasn’t reached pandemic levels, it remains a concern due to its potential to spread. However, there has been no widespread community transmission in China.
9. Hantavirus
Symptoms: Fever, muscle aches, fatigue, and in severe cases, hemorrhagic fever with renal syndrome (HFRS) or pulmonary edema.
Origin: Hantavirus is a significant public health concern in China, where outbreaks of Hantavirus Pulmonary Syndrome (HPS) and Hemorrhagic Fever with Renal Syndrome (HFRS) have been reported. The virus is typically spread by urine, saliva, or faeces of rodents like deer mice (Peromyscus maniculatus), field vole (Microtus fortis), the bank vole (Clethrionomys glareolus), and the rice rat (Rattus rattus).
Impact: Since the 1980s, HFRS has been a major health issue in China, with outbreaks occurring nearly every year, especially during the spring and autumn months when people are more likely to come into contact with rodents. HFRS is more commonly reported across northern and western China where people are exposed to rodents and rodent excretions during farming, hunting, and construction. Hantaan virus is commonly found in mountainous regions and rural areas, where rodents frequently infest agricultural fields. Humans including farmers, soldiers, and forestry workers are susceptible to HFRS often due to contact with rodent-infested granaries, warehouses, and crops. HPS cases have been rarer in China but are often connected to outbreaks in the northeast and northwest regions, including Xinjiang and Inner Mongolia. There is no antiviral treatment or vaccine for Hantavirus, and treatment remains supportive. Research into antiviral drugs and vaccines is ongoing but has faced several hurdles.
10. Foot-and-Mouth Disease (FMD)
Symptoms: Foot-and-Mouth Disease (FMD) primarily affects cattle, pigs, and sheep, though it can also impact goats, deer, and other cloven-hoofed animals. Its symptoms include sudden rise in body temperature, often the first sign of infection, blisters or ulcers on the tongue, mouth, teats, and feet (especially around the hooves). These can lead to painful sores and lameness. excessive drooling due to mouth sores, lameness due to painful lesions on the hooves, decreased milk production, mouth ulcers and blisters leading to eating difficult and weight loss and abortion among pregnant animals due to the infection. In severe cases there may be heart lesions or systemic infection, which can lead to death, especially in young animals or those with weakened immune systems.
Origin: Foot-and-Mouth Disease (FMD) belonging to the Picornaviridae family is a highly contagious viral disease that affects cloven-hoofed animals such as cattle, pigs, sheep, goats, and wild ungulates. The virus is highly contagious and spreads through direct contact with infected animals, especially through nasal secretions, saliva, urine, and feces. Indirect contact through contaminated feed, equipment, vehicles, clothing, and even insects. FMD can also spread rapidly in areas with high livestock density, and the virus can remain viable in the environment for extended periods, especially in cool and moist conditions.
Impact: FMD is a recurrent challenge in China which is one of the largest producers and consumers of livestock. While not typically a human health threat, FMD outbreaks have significant economic consequences, especially for livestock farmers, and can affect meat production, milk supply, and trade especially in areas with dense populations of cattle, pigs, and sheep.
Conclusion:
China has played a significant role as the origin or source for emergence for several viral diseases like SARS, H7N9 avian influenza, and the more recent Langya virus. Its dense population, large agricultural sector, and close interactions between humans and animals create a complex environment where zoonotic diseases can emerge and spread. The country’s rapid urbanization and global connectivity further heighten the risk of these viruses becoming pandemics. This underscores the need for enhanced surveillance, early detection, and international cooperation to mitigate the global threat posed by emerging infectious diseases.
