The crucial benefit of methylene blue as a malaria treatment is the speed in which it takes effect. When artemisinin is applied on its own, the malaria parasite can still be transferred back from a human host to a mosquito for around five days. This creates a fairly large window after treatment where a patient may still spread malaria to other people.
Methylene blue, when combined with artemisinin, was shown to reduce the time the parasite can be taken up by mosquitoes to only 48 hours. This reduces the potential for further spread of the disease considerably.
The malaria crisis in India
In India, sprawling urban metropolises allow for rapid spread of malaria if mosquitoes are allowed to flourish. Any medication that can reduce the potential for malaria to spread could therefore be hugely beneficial and could significantly bring down the number of disease cases.
Around 698 million people in India were considered at risk of malaria infection in 2017 by the World Health Organization (WHO). India accounted for seven percent of malaria deaths worldwide. The WHO has suggested that the actual number of cases may be higher than reported due to low surveillance rates.
Despite the considerable risks for malaria outbreaks within India, the Centre remains optimistic regarding its elimination. Marking World Malaria Day on April 25, the government announced its intentions to eliminate the disease from the country by 2030.
Regardless of the treatments available, poor surveillance systems may hinder any attempts to eliminate the disease. The National Institute of Malaria Research agreed with the WHO and stated that Indian surveillance measures were not adequate enough to fully address the issue.
Methylene blue: A potential first-line treatment?
The dye may provide an effective avenue for malaria treatment, as it comes with few side effects at the dosage used in the study. The study noted that the combination therapy was well tolerated among the test subjects and did not produce any severe effects.
The only alarming — though not dangerous — effect of the treatment was that the urine of those taking methylene blue turned a bright blue. Though this would not cause any complications in terms of health, it could be alarming to some, says Teun Bousema, researcher from Radboud University in the Netherlands. Such a visible effect may dissuade some individuals from taking the medication. Others may only take a partial course of the medication if the the change in urine colour causes distress or concern for their health.
The study specifies the need for follow-up investigations to establish the lowest dose in which the malaria parasite is still eradicated without causing the blue urine. Compliance to treatment is vital to ensuring its effectiveness. As such, human trials to establish the lowest effective dose would aid in making the treatment more tolerable for consumption.
Bousema comments on the potential for the treatment, “There are also indications that methylene blue also works well in species that are resistant to certain medicines”. Drug resistant malaria is increasingly causing concern as it could render many currently used treatments ineffective.
The need for preventive measures
However, if India is to eliminate malaria from the country by 2030, it cannot rely on potential future treatments. Current prevention methods such as mosquito nets may be a more effective avenue for reducing disease cases.
Access to these nets in rural areas is lacking. According to Donna Glass of India Partners, “the greatest problems exist in rural villages because the people cannot afford to have what’s called a long-lasting insecticide net”. If current prevention and treatment strategies are not effectively deployed, there is no evidence to suggest that any new treatments would have a significant impact on disease cases.
The treatment does however look to be a promising new development. Both reduced transmission windows following treatment as well as an effective means to combat drug resistance could provide a well needed boon for the fight against malaria, both in India and worldwide.