Latest news with #zoonotic
Al Jazeera
4 days ago
- Health
- Al Jazeera
What is the Nipah virus and is it spreading in southern India?
On July 12, a new deadly Nipah virus infection was confirmed in a 52-year-old man in the Palakkad district of Kerala, marking the tenth instance of Nipah virus spillover (transmission of the pathogen from animals to humans) in the southern Indian state since 2018. This year alone, Kerala has reported four Nipah cases, including two deaths, all within a 50km (30-mile) radius, on the border of the Malappuram and Palakkad districts. The state remains on high alert, with 675 people under surveillance across five districts. Here is what we know about the Nipah virus, its symptoms and how authorities are containing it. What is the Nipah virus? Nipah virus (NiV) is a highly pathogenic zoonotic virus (a virus that can be transmitted from animals to humans) which causes death in 40 to 75 percent of human infected cases. Alongside the Hendra virus, which is found in Australia, NiV is one of the most notable viruses from the henipavirus genus of the paramyxovirus family, responsible for a range of neurological – often respiratory – diseases in humans and animals. Fruit bats of the Pteropodidae family, ubiquitous across Oceania, South and Southeast Asia, and sub-Saharan Africa, are natural reservoirs of the virus, meaning the virus naturally lives and reproduces in these mammals without causing them any harm. The spillover of the virus to humans can happen directly or via intermediate hosts such as pigs or horses, which come into contact with humans. What are the symptoms of the Nipah virus? According to the World Health Organization (WHO), human NiV infections range from asymptomatic infection to acute respiratory infection, seizures and fatal encephalitis (inflammation of the brain). The clinical presentation of NiV infection is neurological, affecting the central nervous system and resulting in acute encephalitis syndrome (AES), characterised by seizures, confusion and loss of consciousness. When the disease advances, it can cause damage to the lungs and can lead to life-threatening acute respiratory distress syndrome (ARDS). The incubation period of the virus is believed to be four to 14 days. Where have there been Nipah virus outbreaks before? The first human NiV infection was recorded in 1998, when pig farmers and butchers from Malaysia and Singapore contracted the virus from infected pigs. The outbreak affected more than 250 individuals and caused more than 100 deaths. There have been subsequent, almost annual outbreaks in Bangladesh since 2001, with human infection traced to the consumption of date palm sap contaminated with urine or saliva from infected fruit bats. In 2014, NiV infections in the Philippines were associated with the slaughter of horses and consumption of infected horse meat. India has reported two outbreaks in West Bengal in 2001 and 2007. In 2018, South India reported its first NiV outbreak in Kerala, when 19 confirmed cases led to 17 deaths. Since then, Kerala has reported NiV spillovers almost every year. What has happened in Kerala? Although Kerala has recorded 10 instances of NiV spillover since 2018, only two of them turned into outbreaks with instances of human-to-human spread. 'We are now reporting single cases of Nipah infections rather than a cluster or outbreak like in 2018,' Thekkumkara Surendran Anish, nodal officer at the Kerala One Health Centre for Nipah Research and Resilience, said. The last six NiV infections in the state have been single-case spillovers with no human-to-human transmission. The recent uptick in recorded cases is down to the strengthened surveillance system in the state, according to Anish. 'Thousands of people die in India every year due to AES or ARDS, [where] we don't know the cause. NiV, in fact, is not a common cause for respiratory and encephalitis syndromes,' he said. 'But in Kerala, because the entire health system is prioritising Nipah, we are detecting more Nipah infections.' At the same time, it is concerning that all four NiV infections in 2025 were reported in a small timeframe within a small area, Anish added. 'Four independent spillover events within a couple of months in a 50km radius suggest a very high presence of infected bats and the virus in the area. 'What it tells us is that in certain geospatial locations in Kerala, there is a high likelihood of Nipah spillovers, primarily because the bats in those localities seem to be highly infectious for a short period during the year.' What is causing the spread of the Nipah virus in Kerala? Unlike in Bangladesh, where there was a dedicated channel for the virus to spill over to humans (contaminated date palm sap), there is no obvious source in Kerala – or, at least, the 'spillover mechanism' so far remains unclear. 'We don't know the exact spillover mechanism, but it seems to be highly sporadic in Kerala. For example, you unknowingly come in contact with an infected bat or its droppings,' Anish said. The commonly accepted cause is spillover from the human consumption of fruits contaminated by bat saliva or urine. However, virological examination of bat-bitten fruits has yielded negative results so far. A new paper by the Indian Council of Medical Research suggests the virus may be airborne. 'Disease-causing microbes have different routes of transmission to reach and infect human hosts,' Thekkekara Jacob John, one of the authors of the paper, and an emeritus professor at the Christian Medical College, Vellore, said. 'One of them is airborne transmission, like in Tuberculosis, whereby microbes float in the air for longer distances and are inhaled far away from the source.' The authors of the paper believe their hypothesis 'accommodates the rare but recurrent spillovers of NiV in Kerala', where there are no mechanical vectors for the virus, such as in Bangladesh or Malaysia. What are the authorities doing to contain the Nipah virus in Kerala? So far, Kerala has been successful in containing the spread of the virus using trace-and-test procedures. Across 10 'spillover events', the case count stands at just 37 infected individuals. The key to this is a strong surveillance system, said Anish. 'When a Nipah case is established, all primary contacts of the patient are immediately traced and monitored under house quarantine. If they test positive for the virus, we immediately start antiviral treatment,' he said. The prophylactic treatment of 'primary contacts' with broad-spectrum antiviral drugs has helped reduce mortality. 'In our experience, if we can treat Nipah early, it can definitely be cured,' Anish said. 'Syndromic surveillance is another crucial aspect, whereby, in hospitals across the state, any patient presenting with AES or ARDS is tested for Nipah,' Anish said. Kerala has been steadily improving its health system. The state now has four labs capable of conducting RT-PCR (Reverse Transcription Polymerase Chain Reaction) tests for detecting active NiV infections. 'It all comes down to political commitment,' Anish said. 'The state ensures that efforts of the entire health system remain focused on Nipah outbreaks.' What is the treatment for Nipah virus? Is there a vaccine in development? The WHO has identified Nipah as a priority disease for its Research and Development Blueprint – a global strategy and preparedness plan for epidemics. The University of Oxford's NiV vaccine, which began in-human trials in January, was granted support from the Priority Medicines (PRIME) scheme of the European Medicines Agency (EMA) in June. However, there are no drugs yet available that specifically target NiV infection. Since there are no approved treatment protocols for NiV, and due to the high risk of mortality, doctors have used broad-spectrum antivirals. Ribavirin is the antiviral of choice, as it has been found to be effective against NiV infections in humans on several occasions. During a 2023 outbreak in Kerala, early application of the antiviral Remdesivir resulted in an improved case fatality rate. Monoclonal antibodies (copies of antibodies, created in a laboratory) have also been used to prevent severe disease manifestations in high-risk individuals. How can we avoid zoonotic viruses like the Nipah virus? According to Anish, NiV is a model case study for a 'one health' approach to combating high-threat pathogens. The one health approach recognises the fact that human health is interlinked with the health of animals and the environment. '[One health] is a combination of three things – human health, animal health and environment health,' Anish said. 'You have to tackle all these things to reduce the chances of zoonotic spillovers such as Nipah.' Approximately 60 percent of emerging human pathogens are zoonoses, transmitted from animals to humans. Ecological disruption and the spread of human populations into wildlife habitats are primary causes for the emergence of these zoonotic viruses. Climate change is another growing concern, with rising temperatures attributed to influencing infections, viral load and human-animal interactions.
Telegraph
27-06-2025
- Health
- Telegraph
WHO: Lab leak cannot be ruled out as Covid source
The report said that the 'weight of available evidence' suggested a zoonotic spillover, but warned investigators could not 'conclude with certainty where and when this occurred'. The WHO has called for an independent review of what research was being carried out in laboratories near the wet market, including biosafety practices and the health of staff prior to the outbreak. Before the pandemic, WIV had collected more than 220 Sars-related coronaviruses, at least 100 of which were never made public. Members of staff were also photographed wearing inadequate levels of personal protective equipment while handling bats. US intelligence also discovered that three researchers at WIV had sought treatment at a hospital after falling ill with Covid-like symptoms in November 2019. In 2023, a US Senate committee inquiry concluded: 'The preponderance of circumstantial evidence supports an unintentional research-related incident.' WIV was stripped of United States government funding the same year after it was determined the laboratory had conducted dangerous experiments that increased the potency of coronaviruses before the pandemic. Dr Marietjie Venter, chairman of the Sago group said: 'Understanding the origins of SARS-CoV-2 and how it sparked a pandemic is needed to help prevent future pandemics, save lives and livelihoods, and reduce global suffering.'
News.com.au
24-06-2025
- Health
- News.com.au
‘Critical implications' for public health after 20 new bat viruses found in China
Scientists have detected 20 new viruses within bats in China – a discovery medical experts warn could have 'critical implications' for public health worldwide. The study, published by the PLOS Pathogens journal, was conducted by researchers who looked inside the kidneys of 142 bats from 10 species, collected over four years across the Yunnan province, in China's southwest. A total of 22 viruses were detected – 20 of which had never been recorded before. Of greatest concern, however, was the other two henipaviruses found in fruit bats living near fruit orchards close to local villages – one of which is now the closest-known relative of the deadly Hendra and Nipah viruses. The pathogens, which can be spread through urine, have mortality rates between 40 and 80 per cent and can cause severe brain inflammation and respiratory disease in humans, as well as posing a significant threat to livestock. Both viruses can be spread through urine – sparking fears about potential fruit contamination, which could then be transmitted to animals or people if they consumed the food. 'These findings broaden our understanding of the bat kidney infectome, underscore critical zoonotic threats, and highlight the need for comprehensive, full-spectrum microbial analyses of previously understudied organs to better assess spillover risks from bat populations,' the study's authors wrote. The discovery 'hold(s) special relevance' to Australia because of its history of Hendra outbreaks linked to bat populations, virologist at Monash University's Malaysian campus, Associate Professor Vinod Balasubramaniam, told The Sydney Morning Herald. Since 1994, when the virus first emerged from fruit bats and swept through racing stables in the Brisbane suburb of Hendra – killing a trainer and 13 horses – there have been 66 known outbreaks across Australia. Four people and dozens of horses have died as a result. 'The similarity between Australian rural environments and Yunnan's orchards near human settlements stresses the urgency of intensified surveillance and biosecurity measures,' Associate Professor Balasubramaniam said. University of Sydney wildlife disease ecologist Dr Alison Peel said this particular finding highlighted the 'potential opportunities for contact' with humans. Research published in 2023 by Dr Peel on Hendra virus spill over in Australia 'has demonstrated clear links between habitat destruction, loss of natural food, and increased spill over risk – so this may also be the case in China', she told The Courier-Mail. The findings carry 'critical implications' for public health in Australia and globally, virologist Dr Yong Gao (Nias) Peng warned. 'While the findings are based on bat kidney samples and do not confirm imminent outbreaks, they reveal how much we still don't know about the microbes bats carry,' Dr Peng said. 'Given Australia's history with Hendra virus outbreaks since its emergence in 1994 to cause multiple fatal infections in horses and humans, this underscores the importance of continued vigilance in rural and peri-urban areas close to bat habitats.' Aussies urged to get Covid booster shot It comes amid increased pleas for Australians to get their Covid booster shot, with a new contagious variant – already spreading overseas – is expected to drive a winter wave across the country. National data showed earlier this month that just over six per cent of Aussies had received a booster shot since the beginning of the year, with 1.3 million Covid vaccine doses administered to people aged 18 and over. 'To know that those rates are down is a worry because we still see people in hospital,' Deakin University Professor and Epidemiology Chair Catherine Bennett told 'While we now thankfully see fewer deaths due to Covid … in 2024, they're still five times higher than influenza. So Covid is still something to worry about.' As we head further into winter, the NB. 1.8.1 variant – a descendant of the Omicron JN. 1 – is expected to become the dominant variant across Australia. 'It's quite infectious. So it's one that's particularly capable of latching on to our respiratory linings,' Professor Bennett said. 'We're seeing it right across the globe and it has that advantage that it's easier to spread and we're not as immune to it. 'So it will be one that drives our winter wave here.'
The Independent
20-06-2025
- Health
- The Independent
Rabies: What you need to know about the disease before going abroad
The recent death of a British woman from rabies after a holiday in Morocco is a sobering reminder of the risks posed by this almost universally fatal disease, once symptoms begin. If you're considering travelling to a country where rabies is endemic, understanding how rabies works – and how to protect yourself – may go a long way in helping you stay safe. Rabies is a zoonotic disease – meaning it is transmitted from animals to humans – and is caused by a viral infection. In 99% of cases the source of the infection is a member of the Canidae family (such as dogs, foxes and wolves). Bats are another animal group strongly associated with rabies, as the virus is endemic in many bat populations. Even in countries that are officially rabies-free, including in their domestic animal populations – such as Australia, Sweden and New Zealand – the virus may still be found in native bat species. Other animals known to transmit rabies include raccoons, cats and skunks. Rabies is caused by lyssaviruses (lit. rage or fury viruses), which are found in the saliva of infected animals. Transmission to humans can occur through bites, scratches or licks to broken skin or mucous membranes, such as those in the mouth. Once inside the body, the virus spreads to eventually reach the nervous system. Because it causes inflammation of the brain and spinal cord, symptoms are primarily neurological, often stemming from damage to the nerve pathways responsible for sensation and muscle control. Patients who develop rabies symptoms often experience altered skin sensation and progressive paralysis. As the virus affects the brain, it can also cause hallucinations and unusual or erratic behaviours. One particularly distinctive symptom – hydrophobia, a serious aversion to water – is believed to result from severe pain and difficulty associated with swallowing. Once rabies symptoms appear, the virus has already caused irreversible damage. At this stage, treatment is limited to supportive intensive care aimed at easing discomfort – such as providing fluids, sedation and relief from pain and seizures. Death typically results from progressive neurological deterioration, which ultimately leads to respiratory failure. It's important to note that rabies symptoms can take several weeks, or even months, to appear. During this incubation period, there may be no signs that prompt people to seek medical help. However, this window is crucial as it offers the best chance to administer treatment and prevent the virus from progressing. Another danger lies in how the virus is transmitted. Even animals that don't appear rabid – the classical frothing mouth and aggressive behaviour, for instance – can still transmit the virus. Rabies can be transmitted through even superficial breaks in the skin, so minor wounds should not be dismissed or treated less seriously. It's also important to remember that bat wounds can often be felt but not seen. This makes them easy to overlook, should there be no bleeding or clear mark on the skin. The vaccine The good news is that there are proven and effective ways to protect yourself from rabies – either before travelling to a higher-risk area, or after possible exposure to an infected animal. Modern rabies vaccines are far easier to administer than older versions, which some may recall – often with discomfort. In the past, treatment involved multiple frequent injections (over 20 in all) into the abdomen using a large needle. This was the case for a friend of mine who grew up in Africa and was one day bitten by a dog just hours after it had been attacked by a hyena. The vaccine can now be given as an injection into a muscle, for instance in the shoulder, and a typical preventative course requires three doses. Since the protective effect can wane with time, booster shots may be needed for some individuals to maintain protection. Sustaining a bite from any animal should always be taken seriously. Aside from rabies, animals carry many potentially harmful bacteria in their mouths, which can cause skin and soft tissue infections – or sepsis if they spread to the bloodstream. First aid and wound treatment is the first port of call, and seeking urgent medical attention for any bites, scratches or licks to exposed skin or mucous membranes sustained abroad. In the UK, this also applies to any injuries sustained from bats. A doctor will evaluate the risk based on the wound, the animal involved, whether the patient has had previous vaccines, and in which country they were bitten, among other things. This will help to guide treatment, which might include vaccines alone or combined with an infusion of immunoglobulin infusions – special antibodies that target the virus. Timing is crucial. The sooner treatment is started, the better the outcome. This is why it is so important to seek medical help immediately. In making the decision whether you should get a vaccine before going on holiday, there are recommendations, but ultimately the choice is individual. Think about what the healthcare is like where you are going and whether you'll be able to get treatment easily if you need it. Vaccines can have side-effects, though these tend to be relatively minor, and the intended benefits vastly exceed the costs. And of course, avoid contact with stray animals while on holiday, despite how tempting it may be to pet them. Several rules of thumb can counteract the dangers of rabies: plan your holiday carefully, seek travel advice from your GP, and always treat animal bites and scrapes seriously.
Yahoo
19-06-2025
- Health
- Yahoo
British holidaymaker dies from rabies: what you need to know about the disease and getting the jab if you're going abroad this summer
The recent death of a British woman from rabies after a holiday in Morocco is a sobering reminder of the risks posed by this almost universally fatal disease, once symptoms begin. If you're considering travelling to a country where rabies is endemic, understanding how rabies works – and how to protect yourself – may go a long way in helping you stay safe. Get your news from actual experts, straight to your inbox. Sign up to our daily newsletter to receive all The Conversation UK's latest coverage of news and research, from politics and business to the arts and sciences. Rabies is a zoonotic disease – meaning it is transmitted from animals to humans – and is caused by a viral infection. In 99% of cases the source of the infection is a member of the canidae family (such as dogs, foxes and wolves). Bats are another animal group strongly associated with rabies, as the virus is endemic in many bat populations. Even in countries that are officially rabies-free, including in their domestic animal populations – such as Australia, Sweden and New Zealand – the virus may still be found in native bat species. Other animals known to transmit rabies include raccoons, cats and skunks. Rabies is caused by lyssaviruses (lit. rage or fury viruses), which are found in the saliva of infected animals. Transmission to humans can occur through bites, scratches or licks to broken skin or mucous membranes, such as those in the mouth. Once inside the body, the virus spreads to eventually reach the nervous system. Because it causes inflammation of the brain and spinal cord, symptoms are primarily neurological, often stemming from damage to the nerve pathways responsible for sensation and muscle control. Patients who develop rabies symptoms often experience altered skin sensation and progressive paralysis. As the virus affects the brain, it can also cause hallucinations, and unusual or erratic behaviours. One particularly distinctive symptom – hydrophobia, a serious aversion to water – is believed to result from severe pain and difficulty associated with swallowing. Once rabies symptoms appear, the virus has already caused irreversible damage. At this stage, treatment is limited to supportive intensive care aimed at easing discomfort – such as providing fluids, sedation and relief from pain and seizures. Death typically results from progressive neurological deterioration, which ultimately leads to respiratory failure. It's important to note that rabies symptoms can take several weeks, or even months, to appear. During this incubation period, there may be no signs that prompt people to seek medical help. However, this window is crucial as it offers the best chance to administer treatment and prevent the virus from progressing. Another danger lies in how the virus is transmitted. Even animals that don't appear rabid – the classical frothing mouth and aggressive behaviour for instance – can still transmit the virus. Rabies can be transmitted through even superficial breaks in the skin, so minor wounds should not be dismissed or treated less seriously. It's also important to remember that bat wounds can often be felt but not seen. This makes them easy to overlook, should there be no bleeding or clear mark on the skin. The good news is that there are proven and effective ways to protect yourself from rabies – either before travelling to a higher-risk area, or after possible exposure to an infected animal. Modern rabies vaccines are far easier to administer than older versions, which some may recall – often with discomfort. In the past, treatment involved multiple frequent injections (over 20 in all) into the abdomen using a large needle. This was the case for a friend of mine who grew up in Africa and was one day bitten by a dog just hours after it had been attacked by a hyena. The vaccine can now be given as an injection into a muscle, for instance in the shoulder, and a typical preventative course requires three doses. Since the protective effect can wane with time, booster shots may be needed for some individuals to maintain protection. Sustaining a bite from any animal should always be taken seriously. Aside from rabies, animals carry many potentially harmful bacteria in their mouths, which can cause skin and soft tissue infections – or sepsis if they spread to the bloodstream. Read more: First aid and wound treatment is the first port of call, and seeking urgent medical attention for any bites, scratches or licks to exposed skin or mucous membranes sustained abroad. In the UK, this also applies to any injuries sustained from bats. A doctor will evaluate the risk based on the wound, the animal involved, whether the patient has had previous vaccines, and in which country they were bitten, among other things. This will help to guide treatment, which might include vaccines alone or combined with an infusion of immunoglobulin infusions – special antibodies that target the virus. Timing is crucial. The sooner treatment is started, the better the outcome. This is why it is so important to seek medical help immediately. In making the decision whether you should get a vaccine before going on holiday, there are recommendations, but ultimately the choice is individual. Think about what the healthcare is like where you are going and whether you'll be able to get treatment easily if you need it. Vaccines can have side-effects, though these tend to be relatively minor, and the intended benefits vastly exceed the costs. And of course avoid contact with stray animals while on holiday, despite how tempting it may be to pet them. Several rules of thumb can counteract the dangers of rabies: plan your holiday carefully, seek travel advice from your GP, and always treat animal bites and scrapes seriously. This article is republished from The Conversation under a Creative Commons license. Read the original article. Dan Baumgardt does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
