Viruses from mosquitos

8 Vector borne viruses in Australia (Arboviruses): Transmitted by mosquitos

Many patients with chronic symptoms of fatigue, pain, arthritis and brain fog may have undetected viruses that can add to their jigsaw puzzle of underlying causes. I find patients have had past viruses such as Ross River, Barmah Forest or Dengue and may not have even known.

I have seen a few patients come back to Australia from Indonesia with Dengue fever lately too. Its good to be mindful of these viruses as the mosquitos increase into summer.

Ross River Virus (RRV):

RRV is transmitted from female mosquitos (not from person to person) and the incubation (when symptoms may appear) is from three days to three weeks after a bite. Often ther person may not have been aware of a mosquito bite or may have forgotten about it.

Some people may never develop symptoms but others can really be knocked back by it. The most common symptoms are flu – like, aches and arthralgia all over the body. Sometimes a fever maybe present and an infected person may get a rash for about a week. The majority of people recover after a week but in others with a compromised immune system it may take months to a year or longer. This virus contributes to chronic fatigue especially if untreated in the early days. This is one virus I often see in test results (IgG positive) of patients suffering from chronic fatigue showing the person had a past infection that they were not even aware of.

Barmah Forest Virus

Similar to Ross River Fever and caused by mosquitos but symptoms may not last as long as RRV symptoms, from a few weeks to 6 months.

Dengue fever

Initial symptoms may occur 3-14 days after an infected mosquito bite. Symptoms may last for a week and be flu-like, fever, aches all over body, headaches, pain behind the eyes, rashes, nausea, fatigue, swollen glands and bleeding nose or gums.

Dengue viruses (DENVs) cause the most common arthropod-borne viral disease in man with 50–100 million infections per year (1).

Representing the fastest spreading tropical illness in the world (2).

Dengue is a viral infection caused by four types of dengue viruses (DENV-1, DENV-2, DENV-3, DENV-4) belonging to the Flavivirdae family.

Dengue fever can cause long term fatigue in some infected people.

Though exact mechanisms of post dengue fatigue syndrome is not known, however, it is believed that cluster of cytokines and host factors are involved in the pathogenesis (3)

A clinical study showed observation represented the first systematic evidence that dengue can result in clinical disease beyond the acute phases of infection (4).

Catching different types of dengue, even years apart, increases the risk of developing severe dengue.

Severe dengue causes bleeding and shock, vomiting, stomach pain, breathing difficulties and can be life threatening. There have been deaths in Queensland from severe dengue. (www.health.qld.gov.au).

THE FOLLOWING VIRUSES ARE LESS COMMON BUT CAN BE MORE SEVERE:

Murray Valley encephalitis virus

“A mosquito-borne encephalitis virus in New Guinea and Australia, where cases of encephalitis sporadically occur in humans and horses. Human epidemics occur in the Murray River Valley of South Eastern Australia in summer, typically following seasons of heavy rainfall with extensive flooding. These conditions encourage explosive increases in numbers of wading birds, which are the principal vertebrate reservoirs of the virus, and of the mosquito vector Culex annulirostris.” (5)

West Nile virus

“Transmitted by the bite of infected mosquitoes. Most people who become infected have mild or no symptoms (asymptomatic); 1 in 5 patients develop fever, and 1 in 150 patients develop central nervous system disease.

A few may develop encephalitis, meningitis, or polio‐like paralysis. Severe encephalitis and death occur most commonly in the elderly.

Transmission occurs between birds and mosquitoes, with humans and horses as incidental hosts. The incubation period ranges from 2 days to 2 weeks.

West Nile virus is found in Africa, Europe, the Middle East, Asia, Australia, and since 1999, in the Americas.

Symptoms may present as febrile illness: fever, fatigue, myalgias, headache, back pain, pharyngitis, nausea, vomiting, diarrhea, abdominal pain, and maculopapular rash, central nervous diseases (CNS) i.e., encephalitis, meningitis, or meningoencephalitis.

Other symptoms may include acute flaccid paralysis, meningismus, stupor, coma, seizures, nausea, vomiting, headache, myoclonus, and cranial nerve abnormalities and rare symptoms are myocarditis, pancreatitis, and hepatitis” (6)

Japanese encephalitis virus

This virus has been found in the Torres Strait Islands and the tip of far north Queensland. Similar symptoms to Murray Valley encephalitis virus.

“Hendra virus formerly referred to as equine morbillivirus, was first identified in Hendra, Australia, in 1995 and was recognized as a zoonotic disease of horses. Hendra virus causes fatal pneumonia and encephalitis in horses and humans. Clinical signs of Hendra virus are similar to AHS. Fruit bats are the reservoir of infection. Disease transmission requires close contact with infected horses or bat excrement. Hendra virus is classified as a Hazard Group 4 pathogen, which requires the highest level of biosecurity procedures” (7).

Lyssavirus is a bat virus that can infect humans

“Australian bat lyssavirus (ABLV) is closely related to the rabies virus, which does not currently occur in Australia. ABLV has been previously found in bat populations in Victoria, New South Wales, Queensland, Western Australia and the Northern Territory.

Due to the risk of severe disease, people should assume all bats across Australia are potentially infected with ABLV. Symptoms of ABLV can appear within days, or up to several years after exposure. Early symptoms of ABLV infection are flu-like and can include headache, fever, weakness and fatigue. The illness progresses rapidly to paralysis, delirium, convulsions and death, usually within a week or two of symptom onset.

ABLV in humans is almost always fatal once symptoms develop. All three known cases of ABLV in humans have been fatal. ABLV is transmitted by the saliva of infected bats either through bites or scratches, or being exposed to saliva via the eyes, nose, mouth or broken skin” (8).

FOR Tick borne infections go to Amina’s website: www.lymenatural.com

Treatments:

Herbal medicine (immune support and anti viral herbs), nutrition and adopting healthier lifestyle yips may help build the immune system for a stronger resistance to their effects.

For Skype or Clinic Consultations with Amina go to online bookings @ www.noosaholistichealth.com

Prevention: Be mindful of mosquitos! Close windows before the evening comes or have fly screens, wear repellants, discourage mosquito reproduction with pooling water outside homes, wear long sleeves and pants when in forest areas or where mosquitos are present.

References

Anne Tuiskunen Bäck, PhD and Åke Lundkvist, Professor^,Infect Ecol Epidemiol. 2013; 3: Dengue viruses – an overview
Guo-Hong Li et al, Front Cell Infect Microbiol. 2017; 7: 449. Neurological Manifestations of Dengue Infection
Umakanth M.; Saudi J. Med. Pharm. Sci.; Vol-3, Iss-8 (Aug, 2017):858-861
Seet RC¹, Quek AM, Lim EC.
J Clin Virol.2007 Jan;38(1):1-6. Epub 2006 Nov 29.Post-infectious fatigue syndrome in dengue infection.