Introduction

Recently, viral outbreaks have been a primary concern for countries worldwide. The flu virus causes many deaths each year, the COVID-19 coronavirus pandemic accelerated deaths exponentially, and now the hantavirus has become a further cause for concern.^1,2 It previously only impacted remote regions, but now, urban areas are increasingly affected by this virus, so governments may look to take a proactive approach for outbreak prevention. By understanding viral patterns, we can identify critical gaps in prevention and control measures and explore novel ways to curb future outbreaks. But first, let’s explore the hantavirus pathogen in more detail to allow us to better understand the threats it can pose to society.

What is Hantavirus?

Hantavirus refers to a family of viruses that can be transmitted to humans via rodents (rats and mice most commonly), which can cause severe and sometimes fatal illnesses. During the Korean wars in the mid-1900s, soldiers living in trenches first suffered outbreaks of hantavirus diseases due to their close contact with mice and rats in the fields.³ Since then, hantavirus has been studied and described as a pathogen worldwide, causing 2 main types of illness. On the American continents, the main disorder caused by hantavirus is hantavirus pulmonary syndrome (HPS), sometimes called hantavirus cardiopulmonary syndrome because of its downstream effects on the heart.^4,5 On the other hand, in Europe and Asia, the virus more commonly causes haemorrhagic fever with renal syndrome (HFRS)countries.⁵

Figure 1: (5) Global distribution of hantavirus illnesses.

The spread of hantaviruses is very rare between infected humans. More commonly, droppings, saliva or urine from infected mice or rats mix with aerosols (tiny particles dispersed in the air) and cause disease when inhaled by humans. Dust from rodent nests around homes or at farms can also transmit the disease, and rarely, direct contact for long periods with infected rodents can also cause transmission, for example, in the case of the Andes hantavirus in South America.⁶

How do hantaviruses cause illnesses?

HPS and HFRS are both caused by hantaviruses. Initially, the virus attacks parts of your blood vessel lining and your immune cells that help your body fight against illness, like macrophages and platelets. The immune system is triggered, which leads to a cascade of effects that cause your blood vessels to become leaky and cause inflammation. In HFRS, this immune response mostly impacts the kidneys, causing them to leak protein into your urine (proteinuria), fevers, and in extreme cases, acute kidney failure and consequent blood pressure irregularities. Other types of hantavirus can attack the same types of cells but in other parts of the body, like the lungs, which is what happens in HPS. Here, the blood vessels are also affected, and activation of the immune system can lead to fluid build-up in the lungs, restricting air flow into the lungs, which can reduce oxygen levels in your body. This can cause you to feel short of breath and may lead to many other respiratory issues. Eventually, it can cause your lungs to fail quite quickly, and in some cases, fatally.

Although the same types of cells are affected in both illnesses, they each lead to different symptoms and downstream effects.⁴ This is due to slightly different viruses existing in different geographic locations and different human genetics in different ethnicities. Understanding how hantavirus affects the body is essential for developing better treatments, as no specific antiviral therapies currently exist for these conditions.

Treatment options for Hantavirus

Supportive care, in the form of rest and hydration, is the primary approach to managing illnesses caused by hantaviruses, with early recognition and intervention often leading to better outcomes and reducing the risk of complications. Antiviral and other clinical trial treatments are currently underway in the form of inactivated virus vaccines, DNA vaccines, and recombinant protein vaccines. Nevertheless, limited animal models for testing complicate the process, although a general-use vaccine could have an important positive protective effect, especially for high-risk populations.

Currently, supportive critical care focuses on stabilizing fluid (water) and electrolyte (salt) levels in the body; in severe cases, HFRS may require dialysis to filter the blood, and HPS may involve mechanical ventilation or supplemental oxygenation to support breathing.⁴ Experimental treatments like ribavirin, favipiravir, and lactoferrin have shown some effectiveness in animal models, with ribavirin improving survival rates in certain cases of HFRS and HPS.⁴ Vandetanib, a tyrosine kinase inhibitor, has also shown potential in reducing lung damage by improving blood vessel structure, although negative side-effects limit its use.⁴ Immunotherapy with neutralizing antibodies has been explored, with some success in animal models and limited human trials. Additionally, corticosteroids have been tested but have not proven effective in reducing mortality in HPS cases.⁴

Prevention

Prevention remains a cornerstone of hantavirus management, given the lack of currently available treatments. Reducing exposure to rodents and their droppings is crucial in minimizing transmission risk, especially in endemic regions. This can be achieved through various efforts:

•  Keeping clean homes
•  Clearing rodent nests from around homes, farms and establishments
•  Safe storage of food
•  Sealing rodent entryways into homes

Strategies for managing Hantavirus outbreaks

Effectively managing hantavirus outbreaks requires a comprehensive approach that combines surveillance, environmental control, public awareness, and healthcare readiness. By focusing on preventing human exposure, improving outbreak detection, and enhancing community and healthcare responses, the impact of hantavirus outbreaks can be minimized.

Enhanced surveillance and early detection

Quickly identifying hantavirus cases is crucial for containing outbreaks and initiating preventative measures. Regular monitoring by healthcare services can help identify and contain hantavirus cases swiftly, especially in high-risk areas with rodent infestations. Surveillance efforts may include tracking rodent populations and infection rates to predict and respond proactively to potential outbreaks. Additionally, hospitals and clinics in endemic regions should be given guidance on how to recognize the early symptoms of hantavirus since early diagnosis improves patient outcomes and reduces the risk of undetected transmission.

Rodent control and habitat management

Reducing human-rodent contact is fundamental in hantavirus prevention. Effective rodent control measures can limit the virus’s spread by focusing on rodent population management around homes, workplaces, and recreational areas. For instance, communities can implement programs to seal homes and buildings, eliminate rodent food sources, and reduce clutter that might attract rodents. In agricultural or forested areas, environmental management—such as removing debris, maintaining short grass, and controlling grain storage—can reduce the presence of rodent nests. These interventions decrease the chance of humans coming into contact with infected rodents and their droppings.

Public education and community engagement

Educating the public about hantavirus is also key in managing outbreaks. Public health campaigns should inform local citizens, especially those in high-risk areas, about how hantavirus spreads, the importance of rodent control and personal protective measures.

Many aspects may be covered in this effort; for example, people should be educated on safe cleaning practices in areas potentially contaminated by rodents, such as using disinfectants, avoiding actions that raise dust, and wearing gloves and masks. Schools, workplaces, community centres and healthcare centres can act as educational platforms for spreading accurate information and promoting preventative behaviours.

Strengthening healthcare response and resources

A further way to improve patient outcomes is to ensure that healthcare institutions have adequate facilities which are equipped to handle hantavirus outbreaks. For example, hospitals in endemic regions should have the means to monitor and treat hantavirus infections and have enough intensive care units for respiratory support in cases of HPS. Adequate training should be provided to all healthcare professionals in at-risk areas so early signs and symptoms of hantavirus can be recognised quickly. Additionally, the swift application of supportive care techniques and the implementation of infection control procedures can reduce the severity of cases. In deprived areas where this isn’t an option, telemedicine and remote consultations can aid in early diagnosis and management where healthcare access is limited.

Research and vaccine development

Investment in hantavirus research is essential to improving outbreak management and individual patient care. Developing effective antiviral treatments and vaccines could transform our ability to manage hantavirus. Government and international health organisations can support research initiatives to better understand the virus’s behaviour, develop treatments, and accelerate vaccine research. A proactive approach that encourages collaboration among researchers, public health officials, and communities will be key in the advancement of prevention and treatment options.

International collaboration and data sharing

Hantavirus outbreaks are typically region-specific but can spread across borders, especially with global travel and environmental change. International cooperation between health organisations like the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and regional public health agencies is essential. By sharing data on surveillance, research insights, and effective management practices, these collaborations ensure that high-risk areas benefit from global expertise and resources. Cross-border collaboration can also facilitate rapid responses to emerging outbreaks and enable coordinated preventative measures.

Summary

Hantavirus outbreaks pose serious health risks in remote and urban areas, prompting proactive management efforts. Spread primarily through exposure to infected rodent droppings and urine, hantavirus infections can lead to severe illnesses like hantavirus pulmonary syndrome (HPS) and haemorrhagic fever with renal syndrome (HFRS). Control strategies focus on preventative measures, early detection, and effective healthcare responses, while ongoing research explores antiviral treatments and vaccines. Cross-border collaborations are vital in sharing insights and bolstering regional defences against potential outbreaks.