Minnie's Blog

May Blog-Cutaneous Larva Migrans



Cutaneous Larva Migrans
The Virtual Doctors Work
Exciting times for the Virtual Doctors. We have recently expanded so we can reach more Clinical Officers’ in Zambia. This means we are reaching further south in the southern province to cover Zimba and Kalomo districts. This month’s case comes from Simwatachela rural health clinic in the Zimba district.
So let’s travel down the river and explore a little of Zimba district.


Zimba with Simwatachela highlighted in bright green
Zimba is about 410km south-East of the capital Lusaka travelling on the Great North Road. Kalomo district, to which Zimba was a sub-district until 2012, lies on its northern border. Zimbabwe and the great Zambezi River lie to the south and east. Zimba district covers an area of 5000 sq km. Its population is approximately 67000 according to the 2010 consensus. Simwatachela covers 386 sq km and has a population of around 6000 but the population will have grown significantly since then.
Zimbo district is very rural with many villages and settlement –like farms. Agriculture is the main source of work from cattle rearing to crop production. The land supports maize, sunflowers, tobacco and groundnuts. All are dependent on good rainfall so its yield fluctuates.
Described as a Savanah woodland, Zimba is 1300m above sea level with dambo areas, pans and man-made dams. Dambos are complex shallow wetlands which are generally found in higher rainfall flat plateau areas. They usually flood during the rains and are especially important in maintaining the water table, so they are affectionately known as the ‘sponges’, retaining water throughout the dry season providing a much needed water supply and attract a wide variety of wildlife.

This is an example of a dambo in Kafue but they are similar across Zambia.
Zimba faces challenges in terms of infrastructure, housing and roads, but being close to Livingstone, the tourism capital of Zambia, there is great potential for tourism to development in this area. There are protected areas too including the Zimba Hills Local Forest and idyllic beach locations along the Zambezi perfect to attract the adventurous and curious. The Zimba hills local forest covers an area of 18800 hectares and is about 40km south west of Zimba town.

Virtual Doctors support 10 Rural Health Centres, the Zimba mission hospital and Zimba’s district health office in Zimba District

One of the many patients to visit Simwatachela Rural health centre this month was a mother with her 10 month baby boy. Seven days ago she had noticed a raised area like a worm under his skin which moves and grows. It was very itchy and there were multiple sores. The Clinical Officer could see pus coming from the wound and a visible head of a worm. He sent the volunteer doctor a helpful picture and wanted to know what to do next. Amazingly there was a similar case seen in the Naluja RHC in Kalomo district.

Example of a dambo (in Kafue)


The case in Samwatachela

Our GP volunteer doctor replied remarking how he had seen a simiar case from Naluja the same week. He felt this was probably Larva migrans (a hookworm infection) or Larva currens (a threadworm inf

The case in Naluja

ection) and advised treatment with mebendazole or albendazole for 3 days. He was also going to get an opinion from a skin specialist to make sure we had the right diagnosis.
What is Cutaneous Larva Migrans?
Cutaneous Larva migrans is a parasitic skin infection in humans caused by various nematode parasites of the hookworm family (Ancylostomatidae). Humans are incidental hosts of this parasite which normally live in dogs, cats and wild animals and should not be confused with other members of the hookworm family for which humans are definitive hosts! Namely Ancylostoma duodenale and Necator americanus. But sometimes humans become infected with the hook worm larvae by walking barefoot on a beach, or by contact with soil contaminated with animal faeces.
The larvae that come into contact with the skin can penetrate through hair follicles or tiny skin cracks and then migrate under the skin. They can’t penetrate the dermis (the thick layer of skin under the epidermis which contains the blood vessels and nerves) in humans so remain in the outer layers of skin of the human and cannot complete their life cycle.
How does it present?
The most common areas of hookworm penetration are feet, hands, knees, abdomen and buttocks. There is sometimes a non-specific red area at the site of entry of the larvae. It can remain dormant for months or start migrating straight away. When this happens raised pink, or flesh-coloured tortuous snake like tracts that are2-3mm wide form. This is caused by an allergic immune response to the larvae or its by-products.
Tracts can advance between 2mm-2cm a day. These skin lesions are intensely itchy, causing the patient to scratch resulting in sores as we can see in the pictures above.
How do we treat it?
Cutaneous Larva migrans is usually a self-limiting but can be treated with albendazole or ivermectin (antihelmintic drugs). Most cases will resolve within 4-8 weeks as the larvae cannot reproduce so eventually die.
Antihistamines and topical corticosteroids can help to treat the itch.
Secondary skin infection, as seen in our cases, may need treating with antibiotics.
Löfflers disease. This can occur if there is a heavy infestation of larvae and is a combination of pulmonary (lung) infiltrates and eosinophilia.


Skin conditions are a large part of the work at Virtual Doctors and we are able to view great photos of these conditions sent by the Clinical Officers. If there are any skin specialists out there who read this blog and fancy joining the team please contact us!
Disclaimer: This article is for information only and shouldn’t be used for diagnosis or treatment of medical conditions. If you have any concerns about your health consult a doctor or other health professional. 

Minnie's Blog

February’s blog-Osteomyelitis

Please have a read of February’s blog-Osteomyelitis by clicking on the link below



Minnie's Blog


I hope you have had a very happy Christmas. Now  we can look forward to 2018 and how we can make virtual doctors even better and relevant to you. The cases you send us are interesting and often very educational for us in the U.K. too.

The idea of the blog, the cases from the field, that I write, is to give a flavour of the work that you ,the clinical officers, do. I hope to put it in some context for those interested in reading about the virtual doctors work. It is put on the Virtual Doctors website.  I am aware that I probably don’t get all the facts right! So please let me know about your homeland- the highlights, the challenges and where I’ve got muddled up geographically! My aim is make the blog as authentic as possible so I need your help!

If you can, please leave me a comment here- short or long.

many thanks for your help


Minnie's Blog


Please have a read of this month’s blog on Pre-eclampsia.

pre eclampsia blog

Minnie's Blog


Shingles-blog october

Please click on link to read

Minnie's Blog


As we move from Summer to Autumn in the UK and we see rain causing so much disruption and devastation around the world, I wondered about the effects of the changing seasons on health in Zambia. Situated in the tropics, Zambia gets lots of strong sunlight, but the intense heat that comes in the tropics is moderated here by the altitude and rainfall. There are two main seasons in Zambia, the rainy season (November to April), and the dry season (May to October/November). The dry season is divided into a cool and a hot time. The rainy and dry seasons are clearly distinct- with no rain falling at all in June, July and August (usually) followed by hot, wet downpours. Much of life is dominated by the start and end of the rainy season or ‘emerald season’ as it is known and the amount of water it brings. Failure of the rains to come can cause famine. The highest rainfall is in the north with the driest areas in the far southwest and the Luangwa River. Rainfall varies over a range of 500- 1400mm per year.

Flooding occurs every year on the floodplains. Those living in these areas, both people and wildlife, are well adapted to cope with this. However untarred roads become quagmires, many completely impassable. Rivers swell and burst their banks washing away trees, roads and bridges. Many rural areas can be cut off for a few months, making getting anywhere away from the main routes very difficult!

For this month’s case we return again to the Lusaka province which sits on the Zambezi flood plains. This time to Kanakantapa Rural District Health Centre in Chongwe district. Kanakantapa Rural Health Centre serves over 13,000 people from the surrounding communities which are predominantly farming areas. The Kanakantapa river lies to the west of Kanakantapa. It is crossable in the dry season but during the rainy season when the water levels rise and as there is no bridge it becomes impassable, increasing the distance to get to Chongwe by 5 km.

To this clinic, a mother brought her 2 year 11 month old boy to be seen. He is suffering from sores on his feet which have a watery discharge. These sores apparently often returning during the rainy season. The clinical officer (CO) had seen quite a few cases like this and was struggling to treat them. For this child he had tried 2 courses of antibiotics; one oral and the next intramuscular (injection into the muscle) with no improvement. The CO included some good quality photos. These are so helpful in skin cases.


The Virtual Doctor (VDr) wasn’t entirely sure what the diagnosis was. But, as it was a particular rainy season problem and antibiotics hadn’t worked, thought it was likely to be a fungal infection. She advised starting some antifugal medicine by mouth. The advice was gratefully received although the clinic had limited supplies so the CO would have to order some medication to be sent. Tricky in the rainy season.

Meanwhile the VDr asked for a second opinion from a dermatologist in the UK. This condition is something not seen in the UK. The dermatologist thought that is was most likely to be Mycetoma. Advice was for further investigation to distinguish between a bacterial and fungal cause by taking a potassium hydroxide slide of the discharge and seeing if fungal elements or filamentous bacteria could be seen under a microscope. A relatively low tech investigation to perform. And then to treat with antifungal medication if fungus was seen. The nails on the patients left foot looked abnormal  (dystrophic), suggesting a fungal infection. The dermatologist suggested trying treatment but noted that the response to treatment in this infection is generally poor.

What is Mycetoma?

Mycetoma is an uncommon chronic, infective skin and subcutaneous (tissues beneath the skin) disease. It presents with painless lumps under the skin, starting small they can grow, break down and form sores which ooze pus. It can cause the affected limb to become deformed or unusable. If left untreated or treatment fails, it can spread to other areas of the body. Sometimes surgery is needed to cut away infected tissue. Long- term it can destroy underlying muscle and bone. It most commonly affects the foot and it is also known as ‘Madura foot’ after the Indian region where it was first described in 1842. It is a health problem in equatorial regions of Africa, Latin America and Asia known as the ‘mycetoma belt’.

What Causes Mycetoma?

The source of this infection is found in the soil and water and is caused by certain types of both bacteria and fungi. It is likely they enter the body through breaks in the skin. Typically it presents in agricultural workers or those who walk barefoot. It develops over time as it requires repeated exposure of broken skin to the soil and water that contains the microbes. Fungal mycetoma (eumycetoma) is the most common type in Africa. Mycetoma does not spread between people.

Diagnosis and Treatment.

Mycetoma is best diagnosed by taking a small sample (biopsy) of the affected area of the body or the discharge and examined under a microscope to help determine if the infection is caused by bacteria or fungi. Cultures (growing the bacteria or fungi in a laboratory) from the discharge or biopsy can determine the specific type of microbe. Further imaging maybe needed to see how much damage to underlying muscle and bone has occurred.

Treatment depends on whether it is a bacterial or fungal cause:

Bacterial or Actimomycetoma is usually treated with antibiotics and surgery generally not required.

Fungal or Eumycetoma is treated with long term anti-fungal medication, but sadly treatment may not be completely effective. If this is the case then surgery or amputation are sometimes needed.

So early diagnosis and treatment is vitally important and wearing shoes might help to prevent Mycetoma.


Disclaimer: This article is for information only and shouldn’t be used for diagnosis or treatment of medical conditions. If you have any concerns about your health consult a doctor or other health professional.