TropSoc goes national!

We are pleased to announce that the Peninsula Society of Tropical Medicine is now working with students at Hull York Medical School in order to establish a second Society of Tropical Medicine there. Both the Peninsula Society of Tropical Medicine, the Hull York Society of Tropical Medicine and all future chapters will now be part of TropSoc UK, an over-arching organisation tieing the student societies of tropical medicine together.

This means a new site is coming soon with the possibility of more chapter and national events in the coming months and years!

Until then you can visit our placeholder site at: http://thesstm.wordpress.com/

And check out the newly created Hull York Society of Tropical Medicine which will begin operation sometime later this year: http://hystm.wordpress.com/

We hope you are all well! We’ll keep you all posted of these exciting new developments.

Event postponed

“Ebola & Viral Hemorrhagic Fever” with Dr Matthias Borchert has been post-poned until March/April due to issues with telematic linking and the speaker being urgently needed to help meet an EU research proposal deadline. Sorry about that guys!

Next talk: “Ebola & Viral Hemorrhagic Fever” – Dr Matthias Borchert POSTPONED

Our next talk will be “Ebola & Viral Hemorrhagic Fever” by Dr Matthias Borchert of the London School of Hygiene & tropical Medicine at 5:30pm on the 14th of January (venues coming soon). This event will, of course, be absolutely free so anyone is welcome to come along.

Ebola is one of the most notorious infectious diseases in the world. With a mortality rate as high as 50-89% and symptoms such as internal and external bleeding, vomiting blood, abdominal pain and exhaustion, Ebola HF and other viral hemorrhagic fevers are among the most horrifying and lethal infections known to man. Confirmed cases of Ebola Hemorrhagic Fever have occured in the Democratic Republic of the Congo, Gabon, Sudan, the Ivory Coast, Uganda, and the Republic of the Congo and being resistant to most antivirals the spread of the disease is very difficult to contain.

Dr Matthias Borchert of the LSH&TM will talk us through the pathology and treatment of Ebola and other VHFs.

Our next talk will be “Ebola & Viral Hemorrhagic Fever” by Dr Matthias Borchert of the London School of Hygiene & tropical Medicine at 5:30pm on the 14th of January (venues coming soon). This event will, of course, be absolutely free so anyone is welcome to come along.
Ebola is one of the most notorious infectious diseases in the world. With a mortality rate as high as 50-89% and symptoms such as internal and external bleeding, vomiting blood, abdominal pain and exhaustion, Ebola HF and other viral hemorrhagic fevers are among the most horrifying and lethal infections known to man. Confirmed cases of Ebola Hemorrhagic Fever have occured in the Democratic Republic of the Congo, Gabon, Sudan, the Ivory Coast, Uganda, and the Republic of the Congo and being resistant to most antivirals the spread of the disease is very difficult to contain.
Dr Matthias Borchert of the LSH&TM will talk us through the pathology and treatment of Ebola and other VHFs.

Merry Christmas!

Merry Christmas from the whole PSTM team!

Mosquitoes’ sex lives key to malaria

(BBC News) – Scientists believe it may be possible to combat malaria by interfering with the sex lives of the mosquitoes which spread the disease. They have shown that the insects can only mate successfully if the male is able to seal his sperm inside the female using a “mating plug”. Without the plug, fertilisation cannot occur, and the animals cannot reproduce. The Imperial College London study is published in the journal PLoS Biology.

The researchers focused on the species of mosquito primarily responsible for the transmission of malaria in Africa - Anopheles gambiae. These insects mate only once in their lifetime, so disrupting the reproductive process offers a good way of dramatically reducing their numbers. When they mate, the male transfers sperm to the female followed by a coagulated mass of proteins and seminal fluids known as a mating plug. This plug is not found in any other species of mosquito and its role had previously been unclear, but the Imperial team showed it was essential for ensuring sperm is correctly retained in the female’s sperm storage organ, from where she can fertilise eggs over the course of her lifetime.

Anopheles larva from southern Germany, about 8 mm long

In the lab, the researchers were able to stop successful reproduction by preventing the formation of the plug in males.

Professor Steve Lindsay, of the London School of Hygiene and Tropical Medicine, said any attempt to control mosquito populations could be hindered by the fact that the insects’ mating behaviour was still not fully understood.

He said: “This is a very novel idea, which is really neat. We will need a whole variety of different tools to combat malaria, and this may have a function, but there is no one magic bullet.”

A team at the International Atomic Energy Agency (IAEA) are working on another method to reduce the growth of the mosquito population – using radiation to sterilize male insects.

Source: http://news.bbc.co.uk/1/hi/health/8426798.stm

Leprosy Susceptibility Genes Identified; Largest Genome-Wide Association Study of an Infectious Disease

WEDNESDAY, Dec. 16 (HealthDay News) – Seven genes associated with increased susceptibility to leprosy have been identified by scientists in Singapore and China.

The researchers, who analyzed more than 10,000 DNA samples from leprosy patients and healthy people in China, said their discovery highlights the important role that the innate immune response plays in the development of leprosy.

“Though leprosy is not common, the discoveries have significant ramifications for chronic infectious disorders and for host-pathogen interactions in other more prevalent mycobacterial diseases such as tuberculosis,” Dr. Edison Liu, executive director of the Genome Institute of Singapore, said in a news release from the institute.

World distribution of leprosy, 2003

“The discovery of these genes is a major breakthrough for research in leprosy and infectious diseases in general, and will be significant in the early diagnosis and development of new treatments,” study co-leader Jianjun Liu, Human Genetics Group Leader at the institute, said in the release.

The study appears online Dec. 16 in the New England Journal of Medicine.

The genes are: CCDC122, C13orf31, NOD2, TNFSF15, HLA-DR, RIPK2 and LRRK2.

Leprosy is a chronic infectious disease caused by the bacterium Mycobacterium leprae. The disease, which mainly affects skin and peripheral nerves, is rare in developed countries, but remains a major public health problem in many developing countries. According to the World Health Organization, 254,525 new cases of leprosy were diagnosed in 2007.

In regions where leprosy is common, many people are exposed but only a few become infected and develop clinical signs of leprosy, which indicates that only certain people are susceptible to the disease.

Source: http://www.healthday.com/Article.asp?AID=634092

Slides for “The Immunology of Leprosy”

Thanks to everyone who turned up to our second talk, the Immunology of Leprosy by the wonderful Dr Sara Atkinson of the London School of Hygiene & Tropical Medicine. We got a brilliant turnout despite the cold and the talk was excellent!

For those that weren’t able to make it, Sara has kindly allowed us to provide you with a copy of the lecture slides:

The Immunology of Leprosy – Dr Sara Atkinson

Leprosy is a chronic bacterial disease affecting mainly skin and nerves. If untreated, there can be progressive and permanent damage to the skin, nerves, limbs and eyes. Worldwide, two to three million people are estimated to be permanently disabled because of leprosy, mostly in tropical and subtropical worlds with the majority of cases found in India, Brazil and Burma.

17/12/09: The Immunology of Leprosy ~ Dr Sara Atkinson

Our next talk will be “The Immunology of Leprosy” by Dr Sara Atkinson. Sara is coming over from the London School of Hygiene and Tropical Medicine and we’re expecting a really interesting talk on one the most infamous disease of the past 4,000 years!

Leprosy is a chronic bacterial disease affecting mainly skin and nerves. If untreated, there can be progressive and permanent damage to the skin, nerves, limbs and eyes. Worldwide, two to three million people are estimated to be permanently disabled because of leprosy, mostly in tropical and subtropical worlds with the majority of cases found in India, Brazil and Burma. We’ll explore this debilitating disease from the angle of immunology with Dr Sara Atkinson of the London School of Hygiene and Tropical Medicine.

Some disappointing news for Plymouth and Truro members, due to issues arranging support from the AV team experienced by us and many of the other societies we are unable to stream this lecture to your sites.

This talk will be held in Wonford PMS lecture theatre, Exeter at 5:30pm. If any of you would like to come down from Plym/Truro please feel free! Apologies for this situation, it was out of our control and all the rest of our talks are scheduled to be streamed across all sites.

HIV vaccine clinical trials in India reach final stages

Clinical trials for phase one of the HIV/AIDS vaccine being developed in India enter the final stage this month with scientists from the Tuberculosis Research Centre (TRC), Chennai, and the National AIDS Research Institute (NARI), Pune, giving the last round of shots to 32 candidates enrolled in trials.

“For the next World AIDS Day, we will probably have the answer to how close we are to bringing out an efficient vaccine for prevention of HIV/AIDS,” said V D Ramanathan, principal investigator of the study, in an interview to The Times of India on the eve of World AIDS Day. The trial, one among the approximately 150 trials currently underway worldwide, combines a DNA and vector-based vaccine for the dreaded disease.

In August 2008, when the TRC reported the first significant progress in the clinical trials of the vaccine, it was only a vector-based vaccine and scientists said the results could be improved substantially.

The prototype was an MVA (vector)-based potential AIDS vaccine (TBC-M4), which was developed by Kolkata-based scientist Sekhar Chakrabarti. The results showed that it was safe and generated some immunity. “We were happy as for the first time the vaccine had been proven safe and had shown some stimulating immune response. But we thought immunity in the volunteers was not adequate enough to prevent infection, and we saw even that level of immunity reducing after one year,” Ramanathan said. The current study aims to improve upon the results achieved with the vector-based vaccine.

For the second round of trials, TRC and NARI have recruited 16 healthy volunteers. Of these, six have already received two shots of the DNA vaccine at the beginning of the trial and subsequently after a month, followed by the MVA vaccine in the third month; six received two doses of the MVA vaccine. All of them will receive the last shot of MVA this month. Four other volunteers would receive placebos (shots of saline water). “The purpose of doing this is to ensure that the researcher has no prejudice towards the results,” he said.

In September, researchers announced one of the first breakthroughs when they revealed that a two-vaccine combination cut the risk of becoming affected with HIV by more than 31% in a trial of over 16,000 volunteers in Thailand. To date, there have been at least nine MVA vaccine candidates that have been tested or are being tested in labs around the world. Indian scientists hope they will be able to make significant strides if the vaccines prove efficient in phase 1.

Source: Times of India

Study Reveals How Malaria Outwits Host Immune System

A new study has revealed that malaria parasites are able to outwit the host’s immune system.

Malaria is caused by a parasite, which is injected into the bloodstream from the salivary glands of infected mosquitoes. There are different species of parasite, but the most dangerous is the Plasmodium falciparum parasite, which contributes for 90% of deaths from malaria.

The malaria parasite infects healthy red blood cells, where it reproduces. The P. falciparum parasite produces a family of molecules, called PfEMP1, that are inserted into the surface of the infected red blood cells. The cells become sticky and stick to the walls of blood vessels in tissues. This not only stops the cells being flushed through the spleen, where the parasites would be obliterated by the immune system of the body, but also restricts blood supply to important organs. Each parasite has ‘recipes’ for about 60 different types of PfEMP1 molecule in its genes.

The life cycle of Plasmodium

However, the exact recipes vary from one parasite to the other. Hence every new infection may hold a set of molecules that the immune system has not earlier come across. Dr George Warimwe and team from the Kenya Medical Research Institute (KEMRI)-Wellcome Trust Programme and the Wellcome Trust Sanger Institute, have revealed that the parasites get used to their molecules depending on which antibodies it meets in the host’s immune response. They have also found proof to suggest that there may be a limit to the number of molecular types that are actually linked with severe disease.

The researchers examined malaria parasites in blood samples from 217 Kenyan children with malaria. They discovered that a group of genes coding for a particular class of PfEMP1 molecule known as Cys-2  was inclined to be switched on when the children had a low immunity to the parasite; as immunity grows, the parasite switches on a different set of genes, efficiently disguising it so that immune system cannot clear the infection.

Dr Peter Bull from the KEMRI-Wellcome Trust Programme and the University of Oxford, who headed the research, said that the studies could propose a new approach to combating malaria, in terms of both vaccine development and drug involvement. The finding has been published in the journal Proceedings of the National Academy of Sciences.

Source: India-Server

More information: http://www.sciencedaily.com/releases/2009/11/091130151325.htm