Researchers are continuing in their efforts to find an effective vaccine against the novel coronavirus after a breakthrough in Australia suggesting that ivermectin, a widely available and approved anti-parasitic drug also being used in tests to act as a potential treatment for HIV, dengue and Zika among other diseases, could be effective against Covid-19.

The latest research from a team made up of Monash University's Biomedicine Discovery Institute (BDI) and the Peter Doherty Institute of Infection and Immunity indicated that ivermectin could form the basis of a Covid-19 vaccine given that it has proven successful in in vitro tests against other viruses, although human studies will be required to test its efficacy against the coronavirus.

What is ivermectin and what is used for?

Ivermectin was first developed in 1975 and came into medical use in 1981. It is on the World Health Organization's List of Essential Medicines.

It is currently used as a treatment for strongyloidiasis, a parasitic disease caused by roundworms that affects an estimated 30 million to 100 million people worldwide. Ivermectin is effective in destoying the parasites in the intestine.

It is also to alleviate the symptoms of onchocerciasis, or river blindness, which can lead to severe itching, bumps under the skin, and blindness. In the case of river blindness, for which there is no vaccine, ivermectin is not a cure but has been proven to kill the larvae if not the adult worms. It is administered to patients once every six to 12 months.

Ivermectin is also used to treat head lice, scabies and other diseases caused by roundworms and whipworms globally. It is available on the market in drugs including Ivexterm, Ivergot, Dermoper IV, Detebencil, Evanix, Iver P and Ivertal and usually administered in pill form, although it is also manufactured as drops, creams and injectable solutions.

Covid-19 ivermectin tests on humans needed to test effectiveness

Whether it will be effective in the fight against Covid-19 remains to be seen but Dr Kylie Wagstaff from the Monash Biomedicine Discovery Institute said on Thursday: "We found that even a single dose could essentially remove all viral RNA by 48 hours and that even at 24 hours there was a really significant reduction in it."

Dr Wagstaff cautioned that the tests were carried out in vitro and trials would need to be carried out in people to see if the drug was truly effective against Covid-19.