Dubai: Hiking on the mountains and enjoying the last phase of cool weather is a good option, but doctors have cautioned trekkers to be careful lest they catch some irksome larvae through their eyes, ear, nose, or throat, which can cause dire health issues.
This warning comes in light of the unfortunate episode that Isabela Goncalves Moraes, a 23-year old Brazilian expatriate faced.
Moraes, a Dubai resident, who is very health conscious, likes to go on mountain treks during her weekend breaks. She was on one such trek with friends to Ras Al Khaimah on March 14 when she ended up with live larvae of the Bot fly in her eye. If left unattended, the larvae could have burrowed deep down into the eye, impacting the retina and threatening vision loss.
Moraes told Gulf News, “ I had gone on a hike with my friends on March 13 and the area we went to had sheep and other cattle. Perhaps the Botfly was just flying around and it hit my right eye. I immediately felt pain as if some foreign body had entered the eye.”
When the symptoms persisted the next day, with redness pain, swelling, watering and the sensation of having a Foreign Body (FB) in her eye, Moraes reported to the hospital and was referred to the ophthalmology section of Aster Hospital, Mankhool. Dr Vikram Mohindra, Specialist ophthalmologist at the hospital, examined her.
Moraes told the doctor that she felt a sharp sting in her eye while on a trek. After that, she had washed the eye, using water, she used a soft earbud to try to remove the foreign body. However, despite her best efforts her eye kept getting worse.
Larvae detected under microscope
Moraes had brought the sample cotton bud, preserved in sterile solution, which was examined under the microscope. Dr Mohindra told Gulf News, “On gross examination, to me the FB looked suspiciously similar to a Botfly larvae seen in a similar case following a hiking trip, a few years back. Careful history taking revealed that she along with fellow hikers had indeed been to the emirate of RAK on the weekend for hiking.”
Dr Mohindra explained, “In many other instances, it has been found that the female botfly carrying the larvae can also transfer it to a sheep or horse, which then is transferred to human beings. In case of infestation through the eye, the larvae can cause External Ocular Myiasis (infection) EOM. The EOM is not a benign condition and has to be treated promptly by removal of. EOM prevalence rates are low with less than 300 cases reported in the last century. It is essential to extract the larvae while it is still in the external eye because if it goes deep inside, it can proliferate and be a dangerous threat to vision as well.”
Further examination of the eye confirmed the diagnosis. “Mobile, translucent larvae were seen in the conjunctival sac firmly attaching themselves with their sharp hooks,” said Dr Mohindra. “If the eye has live bot fly larvae, the only definitive treatment is to extract the ones seen physically, one by one, under the microscope under local anaesthesia. The next step is to search for the remaining larvae in the external eye. Lastly, one needs to hunt down this larvae from their favourite hiding place around the punctual area (location where eye fluids drain) and remove them one by one. However, despite all care, it is likely that some tiny larvae can be left behind, which can proliferate into the internal eye and cause severe infection and threaten loss on vision too. We therefore, call the patient for repeated examinations to search for any additional larvae. “
Novel technique used
However, in Moraes’ case, these steps did not work out so well as despite local anaesthesia. After repeated attempts, it became clear to Dr Mohindra that extraction would not be possible under local anaesthesia as Moraes was in extreme discomfort and pain.
The team soon became aware that conventional treatment would be difficult if not impossible in her case. Administering general anaesthesia this time and every time the patient came in for re-examination also did not sound like a good option. Therefore, Dr Mohindra thought of a novel technique of the ‘Flooding ‘of conjunctival sac with five per cent Betadine for five minutes to suffocate and drown the seen and unseen larvae, which was implemented right away.
Two dead larvae extracted
The strategy was successful. The fluid used to inundate her eye, was drained collected, strained with filter paper and it showed two dead larvae that appeared as brown stains on the filter paper. The dead larvae were sent for a parasitology examination. Since these perished within five minutes contact time with the iodine solution, the team presumed that others could not have survived.
However, the patient was given a 15-minute eyewash with normal saline and then her eye was re-examined for any leftover larvae. Luckily, nothing was discovered and the patient went home happy. In subsequent follow-ups too no additional larvae was discovered and with a course of antibiotic treatment and Non-Steroid anti- inflammatory drug (NSAID) eye drops as well as ointment helped the eye heal. Moraes expressed relief and happiness with the treatment.
The laboratory examination of the larvae confirmed the foreign body to be the larvae of the Oestrus Ovis or the Bot fly. To be extra cautious, Dr Mohindra prescribed a specific medicine called Ivermectin, which can take care of any residual larvae that may be hiding in deeper recesses of the eye.
Moraes, who had come for a follow-up visit to the hospital on March 29, said, “It’s more than 10 days since I underwent the procedure to extract the larvae. It was very painful and I had to get local anaesthesia at least thrice. I am relieved that the larvae was removed and have been following up closely with Dr Mohindra. Initially I had some pain and discomfort but now I am totally fine. I would like to tell people to be very careful while going on a hike to rural areas. There is sheep and cattle around and the botfly is known to be a parasite looking for a host. Please cover your head and wear eye glasses when trekking.” she said.