Horses and mosquito-borne viruses - McDowell's Herbal Treatments

Mosquitoes can carry diseases that can make people, horses and other animals sick. With the storms, floods above average rainfall seen all around Australia this season, mosquitos and some mosquito-borne diseases are on the rise...

mosquito spray image2

Bites from mosquitos can be more than just an painful itch to your horse. Mosquito bites can also cause skin irritation, allergic reactions, AND transmit diseases. Although your horse's coat does offer a bit of protection, they can still get bitten.

Ross River Fever

Ross River Fever is a viral disease that can effect horses as well as humans. It is an arbovirus, transmitted via biting arthropods which include mosquitos, biting midges, sandflies and ticks. It is named after the Ross River, which flows through Townsville on the northeastern coast of Queensland. 

The virus is transmitted enzootically - between mosquitoes and kangaroos, wallabies, flying foxes, horses, and other vertebrates (4). It is rare, however, for it to be transmitted from horse to human. It can also be called Ross River virus or epidemic polyarthritis. It isn't fatal but some symptoms can continue to effect the horse for months.

Signs of Ross River Fever;

  • Fever
  • Musculoskeletal abnormalities (swollen joints, swelling of the lower limbs)
  • Reluctance to move and lameness
  • Aanemia
  • Lymphopenia (not enough white blood cells)
  • Behavioral changes like lethargy, inappetence, increased lying down 

Japanese Encephalitis

Japanese Encephalitis is making news at the moment as the newest mosquito-borne illness affecting humans and horses (and pigs). It is important to remember not to panic - only about 1% of people who contracted the virus showed any symptoms.

Horse imports from Australia to New Zealand are facing tougher restrictions, as Australia sees rising cases of a potentially deadly virus spread by mosquitoes. While the virus can infect horses (which New Zealand does import), they’re referred to as “dead end hosts” meaning they don’t pass the virus onto mosquitos, humans, or other horses (1).

Signs of Japanese Encephalitis;

  • May appear to have colic
  • Fever or elevated tempreture
  • Jaundice 
  • Stumbling, staggering
  • Depressed
  • Reluctance to move
  • Loss of appetite

Japanese encephalitis disease spread pathway UPD
Image from Department of Agriculture, Water and Environment

West Nile Virus

This infection is expected to occur during late summer and autumn. In Australia, disease has been limited to horses, although several cases have been suspected (though not confirmed) in dogs.

There have now been several deaths and horses infected with West Nile virus in numbers not seen since the outbreak of 2011.

Symptoms of West Nile Virus

Symptoms could vary, but can appear similar to the Hendra virus. These include;

  • Dull and depressed
  • Fever
  • Can appear to have a 'headache'
  • Weakness of limbs
  • Loss of appetite and difficulty swallowing 

What can you do about mosquitos?

  • Clear away any low-lying water from around your home
  • Limit your exposure to mosquitoes by avoiding mosquito habitats such as stagnant water (easier said than done in some places right now!)
  • Cover up with light rugs during peak periods
  • Use insect repellants (natural of course!)
  • Plant herbs and insect repelling plants 
  • Stabling horses between dusk and dawn could help, as the mosquito most likely to carry diseases of concern is a night-time feeder

McDowells Products

Ross River Fever Program
Our Ross River Program consists of four products to be used together to enhance the body's natural healing mechanisms. The herbs in the formulas are traditionally used stimulate the expulsion of infection and viral matter. The program is designed to build gut health, reduce pain and inflammation and with stimulating elimination via normal metabolic process and building a stronger immune system.

The Midge-away formula was developed in response to those seeking a 100% natural NON-TOXIC solution to dealing with flying insects and annoying midges. The product acts by using traditional anti parasitic herbs in a base of raw cider vinegar and Methylated spirits , blended with 1:1 extracts and essential oils. The product is exceedingly safe to use, non toxic and when used correctly helps to discourage insects landing on your dogs coat . The product can also be used as an environment spray.

Infect-A-Clear for horses
The herbs in this mix have been traditionally used to stimulate the horse’s own natural elimination which may help to clear these naturally occurring metabolites thereby improving the immune system's response.


(1) Oz mosquito virus prompts changes to NZ horse imports By Andrew Macfarlane, 1News Australia Correspondent
(2) West Nile Virus Infection Department of Primary Industries
3) Japanese encephalitis in horses Department of Primary industries
4) KER Ross River Virus in Horses October 28, 2020 By Kentucky Equine Research Staff

Have a question? Contact McDowell's Herbal Treatments

Get in Touch

We are open Monday to Friday 9 am to 5 pm. AEST. You can also contact us by phone or email.

02 6331 3937
+61 2 6331 3937(Int)

McDowell's staff Herbalists can not diagnose your disease or illness. What they can do is offer a herbal program to assist with healing, after you have had advice from your doctor or specialist. If you have unexplained pain or symptoms, seek medical advice.

EMAIL info@mcdowellsherbal.com  |  PHONE 02 6331 3937  |  INTERNATIONAL +61 2 6331 3937