UWI Pilots Research in Free Living Amoeba     

Prior to the splashy headlines this summer, which attributed four deaths in southern United States to a brain-eating amoeba, most individuals were genuinely impervious to the presence of such an organism causing infection in humans. In fact, most would believe that such headlines were stolen directly from sci-fi movies.

However, this organism, otherwise referred to as Naegleria fowleri has been around from the 1960s, having been discovered in Australia during that period. Since then, this organism which causes the waterbourne disease called Primary Amoebic Meningoencephalitis has been reported on in 15 countries across five continents and the number of cases has been increasing.

Known to thrive in warm contaminated fresh water ponds, falls, rivers, lakes and swimming pools, this organism affects persons while swimming by entering the body through the nostrils, where it travels to the brain and feasts on it, killing the victim within two weeks.

While the most recent rash of cases in the United States may provide reasons to get jittery especially in light of the fact that Jamaica is considered the land of wood and water, this infection which is invariably fatal, is considered rare. Professor John Lindo, Head of the Department of Microbiology, Mona says its occurrence is akin to that of “being struck by lightning,” which is rare, as the amoeba usually goes after bacteria in the water and also in the soil and not human tissue.

Nevertheless, Professor Lindo says that studies have been launched by The UWI, Mona to determine if the Naegleria species as well as Sappinia genus are present in Jamaican waters with a view to establishing their prevalence. The Sappinia genus, which belongs to the free living amoeba group that normally lives in soil contaminated with faeces of elk, bison and cattle, has been identified as causing encephalitis (swelling of the brain) in an otherwise healthy individual.

“Although we do not consider these free living amoebae (to be) a big public health problem, we really still have no way of quantifying mortality or morbidity rates from amoebae. It is a very interesting group of organisms to study because we know so little about them,” he says.

“We want to look at the range of amoebae that we have here in Jamaica and where they are distributed across the country and their pathogenic potential,” he adds, while noting that questions abound over what makes some free living amoebae more virulent than others and what makes some humans more susceptible to them than others.

Prior to these current studies, the focus of The UWI, Mona since 2003 has always been on the Acanthamoebia genus, another free living amoeba, which causes Acanthamoeba Granulomatous Encephalitis, a rare, chronic progressive infection of the central nervous system that may involve the lungs. It is also usually associated with an underlying debilitating disease or immune suppressed individuals including HIV/AIDS patients; diabetics; organ transplant recipients; patients undergoing chemotherapy; and, drug abusers. This work, in addition to the new studies, are being conducted in conjunction with the University of LaLaguna(ULL) in Spain, a globally recognised leader in the field of study, and is led by Professor Lindo and Dr. Jacob Lorenzo-Morales (Institute of Tropical Medicine, ULL).

“We have a good collaboration with our colleagues in Spain as they back us up in some of the more advanced techniques required in our studies,” Professor Lindo says.

During this eight-year period, samples from water sources from all over Jamaica were collected and Acanthamoebia strains with pathogenic potential to humans and other animals were isolated and these findings were published in the Annals of Tropical Medicine and Parasitology. The research team reported that from the collected samples strains with pathogenic potential were shown as 60 per cent in tap water, 68.4 per cent in river water and 40.3 per cent of the sea water samples. “As you can see Acanthamoeba is very common in Jamaica and we have a lot of it in tap water, rivers and streams. This was revealed in our preliminary report of where it is found in Jamaica,” Professor Lindo explains.

Free-living amebic infections (Source: Centers for Disease Control and Prevention)

Soon after the publication of the preliminary data, the first case of Acanthamoeba keratitis was reported by the research team in a female patient, who was blinded in one eye. This severe infection, which is caused by the Acanthamoeba specie, mostly affects contact lens wearers although there are many cases that have been reported worldwide in non-contact lens users mostly related to a previous corneal trauma. Prevention of this type of infection of the eye in contact lens wearer is dependent upon strict lens hygiene. “Persons should follow the instructions on the manufacturer’s label,” Professor Lindo advises. As the research team continues to forge ahead with sampling in Jamaica in order to check for the presence of other free living amoebae that have not been studied before, Professor Lindo anticipates that in another five years the team will have “a better grasp of the situation and therefore be able to make recommendations of where and what to avoid” as it pertains to free living amoebae.

In the meantime, Jamaica was the destination for the XIV International Meeting on Biology and Pathogencity of Free Living Amoebae (also known as the Irie Amoebae Meeting) at the Iberostar Hotel in Montego Bay, St. James from October 11-15. Organised by UWI, the conference attracted world leading experts from over 20 countries located in Europe, the Americas, Asia and Africa . The world leading scientists and clinicians discussed recent advances in diagnosis, treatment and pathogenicity and basic biology. As a result, the Mona Campus was able to strengthen its research linkages with several key international partners . Plans are now being made for the publication of full papers from the meeting in the prestigious journal Experimental Parasitology and the preparation of students to submit papers to FLAM 2013, to be held in Vienna, Austria.