Rabies is a viral disease that causes inflammation of the brain in humans and other mammals. It is spread through contact with saliva from an infected animal, usually through bites. Rabies has one of the highest case fatality rates of any infectious disease – if left untreated, rabies is almost always fatal. However, rabies is also preventable if vaccination occurs soon after exposure. Globally, rabies causes an estimated 59,000 human deaths annually. Understanding which groups are most vulnerable to rabies can help target prevention and control efforts.
Key Facts About Rabies
- Rabies is caused by lyssaviruses, including the rabies virus and Australian bat lyssavirus.
- It is spread through contact with saliva from an infected animal, usually via bites or scratches.
- Rabies affects mammals, including humans, dogs, bats, raccoons, skunks and foxes.
- Once clinical symptoms appear, rabies is almost always fatal.
- However, timely postexposure prophylaxis is highly effective in preventing the disease if administered before symptoms start.
- Approximately 59,000 people die annually from rabies worldwide.
- Over 95% of human rabies deaths occur in Africa and Asia.
- Children under 15 account for about 40% of postexposure treatments.
These key facts illustrate that rabies disproportionately impacts vulnerable populations, including children and those in lower income regions. But which gender is most affected by this deadly disease?
Males at Higher Risk of Rabies
Research clearly shows that males are more susceptible to rabies than females. Some major points:
- A literature review published in PLOS Neglected Tropical Diseases analyzed data on rabies deaths from the early 1900s through 2015. It found males accounted for 2.5 to 3.5 times more rabies deaths than females globally.
- According to the WHO, rabies deaths occur more frequently in males across all age groups worldwide. The male-to-female ratio averages 3:1 globally but can be as high as 7:1 in Asia.
- A study in Tanzania found nearly 5 times more rabies deaths in males than females over three decades.
- Research from India showed 2.9 times more treated male bite victims than females over 5 years.
- Multiple studies from countries like Turkey, Ethiopia, Nepal and the Philippines also demonstrate significantly higher rabies incidence and deaths in males compared to females.
The data consistently shows males face a substantially higher risk from rabies across different countries, age groups and over various time periods. But why is this the case?
Reasons for Higher Rabies Risk in Males
There are several reasons why rabies disproportionally impacts males more than females:
Greater Exposure to Rabid Animals
Males, particularly in rural settings of developing countries, tend to have more occupational and recreational exposure to animals that may carry rabies.
- Work activities like animal husbandry, farming, and hunting put males at higher risk of rabid animal bites.
- Males more often explore caves, forests and rural areas inhabited by rabies reservoir species like bats, foxes and stray dogs.
- Boys are more inclined to play with and handle unknown animals, increasing their risk of rabid bites.
Underutilization of Postexposure Prophylaxis
Postexposure prophylaxis (PEP) with rabies vaccine and immunoglobulin prevents development of rabies after exposure, but males may be less inclined to seek timely medical treatment.
- Studies show males often delay going to health clinics after potential rabies exposures, reducing PEP effectiveness.
- Cultural and socioeconomic factors may prevent males from promptly getting PEP, such as loss of wages to visit clinics.
- Males may decline PEP due to underestimation of rabies risks from animal bites and scratches.
Biological Factors
Biological differences may also contribute to males’ increased rabies susceptibility.
- Androgen hormones like testosterone could suppress immune function against rabies virus.
- Females may mount more robust immune responses and be less susceptible to rabies due to genetic and hormonal factors.
- However, more research is needed to confirm whether biological mechanisms underlie sex differences in rabies susceptibility and mortality.
Together, occupational exposures, treatment-seeking behaviors and biological traits put males at significantly higher risk of lethal rabies infections globally.
Regional Differences in Rabies and Gender
The male-skewed ratio of rabies deaths is remarkably consistent across different continents. However, some regional trends exist:
Asia
Asia suffers the highest burden of rabies deaths annually. India alone sees about 36% of the world’s rabies deaths, primarily driven by dog bites in rural areas. Studies show the male-to-female ratio of rabies deaths ranges from 3:1 to 7:1 across different Asian countries. Lack of PEP utilization and biological factors likely contribute.
Africa
Africa has the second highest incidence of rabies globally. Studies report male-to-female ratios ranging from 2:1 to 5:1 across African nations. Delayed PEP administration after dog bites drives gender differences.
Americas
Rabies has been largely controlled in North America, but remains endemic in parts of Latin America. Male-to-female ratios are typically lower, ranging from 2:1 to 3:1. Early PEP use prevents deaths.
Europe
Rabies is uncommon in Western Europe but sporadic cases still arise in Eastern Europe. Reported ratios are also lower around 2:1 to 3:1 as timely PEP prevents deaths.
Australia
Australia is one of the few rabies-free regions. But occasional bat lyssavirus cases occur with higher incidence in males due to recreational exposure.
So while the male excess of rabies deaths persists worldwide, prompt PEP administration and biological factors can influence the degree of gender skew across different regions.
Age Differences in Rabies Deaths by Gender
Across studies, rabies incidence and mortality trends differ by age as well as gender:
Children
More rabies deaths overall occur in children under 15, largely related to their inclination to play with animals. The male-to-female ratio ranges from 2:1 to 3:1 in studies. Lack of knowledge on rabies risks contributes.
Adolescents & Young Adults
Bites during occupational or recreational activities lead to more rabies deaths in teenage and young adult males. Reported ratios range from 4:1 to 6:1.
Middle-Aged Adults
Deaths decline in middle age but remain higher in males, typically around 3:1 to 4:1 ratio.
Elderly
Rabies deaths increase in elderly populations as health declines. Ratios are lower, from 2:1 to 3:1, as both elderly males and females have exposures from bites.
So while males of nearly all age groups are at greater risk, certain activities and behavioral factors drive higher gender skews in some age ranges.
Prevention of Rabies Deaths in High-Risk Groups
The disproportionate rabies burden in males presents opportunities to target prevention measures:
- Increase awareness of rabies risks and need for prompt PEP in adolescent and adult males engaging in occupational or recreational animal exposures.
- Ensure rabies education programs also reach women and children in high incidence regions.
- Improve accessibility and affordability of PEP, particularly in rural communities.
- Educate healthcare workers to vigilantly provide PEP to bite victims, including males who may otherwise decline.
- Expand dog vaccination coverage in rabies hotspots to reduce human exposures.
- Conduct operational research to better understand barriers to PEP use across ages, genders, and locations.
Focused efforts on those most vulnerable can save lives and reduce rabies’ unequal gender burden worldwide.
Conclusion
Rabies remains a prevalent and frequently fatal disease globally, responsible for tens of thousands of deaths annually, particularly in Africa and Asia. Extensive research clearly demonstrates males of all age groups face a significantly higher risk of rabies mortality compared to females, with male-to-female ratios typically ranging from 2:1 to 7:1.
Several factors drive this gender discrepancy. Males, especially in rural developing regions, have increased animal bite exposures related to work and recreation. Males also exhibit treatment-seeking behaviors that delay life-saving PEP. Biological differences may also increase male susceptibility.
Ultimately, rabies prevention initiatives should target males of all ages, who bear the greatest burden of this neglected disease. Improving education, PEP access and utilization, and animal vaccination can help reduce the disproportionate impact of rabies on males worldwide.