Showing posts with label doxycycline. Show all posts
Showing posts with label doxycycline. Show all posts

Monday, 4 April 2011

MALARIA: Doxycycline for Malaria Chemoprophylaxis and Treatment:

Doxycycline for Malaria Chemoprophylaxis and Treatment: Report from the CDC Expert Meeting on Malaria Chemoprophylaxis
Kathrine R. Tan*, Alan J. Magill, Monica E. Parise, AND Paul M. Arguin
Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia; Walter Reed Army Institute for Research, Silver Spring, Maryland

Abstract.:
Doxycycline, a synthetically derived tetracycline, is a partially efficacious causal prophylactic (liver stage of Plasmodium) drug and a slow acting blood schizontocidal agent highly effective for the prevention of malaria. When used in conjunction with a fast acting schizontocidal agent, it is also highly effective for malaria treatment. Doxycycline is especially useful as a prophylaxis in areas with chloroquine and multidrug-resistant Plasmodium falciparum malaria. Although not recommended for pregnant women and children < 8 years of age, severe adverse events are rarely reported for doxycycline. This report examines the evidence behind current recommendations for the use of doxycycline for malaria and summarizes the available literature on its safety and tolerability.
http://www.ajtmh.org/cgi/content/abstract/84/4/517?maxtoshow=&hits=23&RESULTFORMAT=&andorexacttitle=and&andorexacttitleabs=and&fulltext=malaria&andorexactfulltext=and&searchid=1&usestrictdates=yes&resourcetype=HWCIT&ct

Monday, 21 February 2011

MALARIA: Malarone in pregnancy

Amy Norton : Feb 16, 2011
NEW YORK (Reuters Health) - Pregnant women who take the anti-malarial drug Malarone during their first trimester might not be increasing their baby's risk of birth defects, a new study suggests.
Most anti-malaria drugs -- including this one -- are not approved for use in pregnancy. So when pregnant women want to travel to malaria-ridden regions, they face a huge problem: should they take preventive medicines that haven't been proven safe for the fetus?
In general, experts advise all pregnant women to avoid traveling to countries where malaria is common, since the infection itself may be dangerous to the mother and fetus.
The new study, published in the Archives of Internal Medicine, is the first to look at pregnant women's use of Malarone -- known generically as atovaquone-proguanil -- and the risk of birth defects.
So the researchers say it is too soon to declare the drug safe for the small number of pregnant women who might need to take it.
The cheapest and mostly widely used anti-malaria drug, called chloroquine, is considered safe during pregnancy. But resistance to that drug has become common worldwide.
Another anti-malaria drug, the antibiotic doxycycline, is known to have adverse effects on the fetus.
In the new study, researchers looked at data on nearly 571,000 births in Denmark between 2000 and 2008. Overall, 2 to 3 out of every 100 newborns had a birth defect.
Among the 149 women who used Malarone at some point during the first trimester, roughly one of every hundred had a baby with a birth defect.
The findings offer some reassurance that the drug is not linked to any large risk of birth defects, said lead researcher Dr. Bjorn Pasternak, of Statens Serum Institute in Copenhagen.
Still, since only a small number of women in the study took Malarone during early pregnancy, the findings cannot rule out the possibility of some risk, Pasternak said.
"We believe it is far too soon to declare this drug to be safe for use in pregnancy," he told Reuters Health in an email.
Malarone is not inexpensive -- it costs close to $200 for 24 pills. The number of pills a woman would have to take depends on how long she stays in the malaria region.
Caused by a mosquito-borne parasite, malaria is widespread (the technical term is "endemic") in large areas of Africa, Asia and South and Central America, where it kills about 1 million people a year.
An estimated 10,000 to 30,000 travelers develop malaria every year, and about 150 die.
http://www.reuters.com/article/2011/02/16/us-malaria-drug-idUSTRE71F66K20110216?feedType=RSS&feedName=healthNews

Sunday, 14 November 2010

MALARIA: Malaria in the Military

 Bill Brieger

11 Nov 2010
nyt-mali-7a.jpg


November 11th is Veteran’s Day in the United States. Over the years soldiers have been vulnerable to malaria. During the U.S. Civil War 150 years ago over 14,000 Union troops are estimated to have died from malaria. While death estimates were not available for the Confederates, it was thought that over 40,000 malaria cases occurred in an 18-month period in the middle of the war.

Today places like Afghanistan and the Horn of Africa pose a malaria threat to troops, so there is malaria prophylaxis for soldiers. Sometimes the prevention itself poses problems. “The Army has dropped Lariam — the drug linked to side effects including suicidal tendencies, anxiety, aggression and paranoia,” and now prefers doxycycline for people who may react to mefloquine.
The military takes malaria seriously now. The Walter Reed Army Institute of Research (WRAIR) puts a priority on malaria research since, “Malaria remains highly relevant to the military because of its prevalence, variety (there are four species that infect humans), debilitating nature, potential lethality, and tendency to become resistant to drugs. No organization in the world has WRAIR’s experience in the complete spectrum of malaria research.”
WRAIR’s “Work on a vaccine is also progressing. Advanced molecular, genetic, and biomedical technologies are now being employed to produce candidate malaria vaccines. Field trials of these candidate pharmaceuticals are an essential part of the program and are underway in Thailand and Kenya.”
The military of all nations are at risk when they serve in malaria endemic areas. For example, a Philippine soldier “succumbed to malaria on 23 October 2008 while serving as a military observer with the U.N. Mission in Sudan.”
Another concern of malaria in the military is the potential for soldiers who contract malaria for spreading it to other countries or bringing it home. It was reported that Soviet soldiers serving in Afghanistan some years ago brought the disease back to republics in the Caucasus and Central Asia. Though this particular spread could be controlled, not all situations may be so fortunate.
Today a variety of injury and mental health problems may overwhelm the effects of malaria on soldiers. Still, soldiers are at risk. For example in 2002, “38 cases of malaria were identifiedin a 725-man Ranger Task Force that deployed to eastern Afghanistan.” Also over a 6-year span the Defense Medical Surveillance System reported 423 cases of malaria including Plasmodium vivax, P. falciparum, P. ovale, and P. malaria. A big challenge is the inability of health systems in non-endemic countries to treat and save lives of soldiers who return home with the disease.
There are basically two lessons from this issue. First malaria control must recognize that soldiers who may not be immune when they enter a malaria endemic war zone are at risk of malaria death. Secondly, as a mobile population soldiers have the potential for reintroducing malaria to areas where it may have been eliminated. War kills people; malaria kills people - when soldiers are infected a double dose of death potentially occurs
http://www.malariafreefuture.org/blog/?p=1080

Sunday, 11 July 2010

MALARIA: personal experience and review

To watch children slip into the potentially fatal clutches of malaria is terrifying. It's the speed of the descent from good health to serious illness that is so frightening: at dawn they are fine, by dusk they could be in a coma, from which they might never wake. I know this because several years ago I was there – panic-stricken – watching my then eight-year old son, his mind drowning in delirium and his young body teetering on the brink of collapse.
He begged me to 'Just let me close my eyes for a bit, mum', and, desperate, I pleaded with him to stay awake. His decline took less than six hours. In the end he was fine – it meant an emergency airlift, an admission to hospital where he was administered artemisinin (a drug derived from the plant Artemesia annua) intravenously, and four long recuperative weeks out of school, but he did make a full recovery. We were lucky, luckier than the parents of the estimated 5,000 children that die from malaria every day.
Malaria is the world's biggest killer. It affects almost 500 million people a year and takes the lives of nearly 3 million – mostly in Africa, where a child is estimated to die from the disease every 30 seconds, at an estimated cost to the economy of more than £6bn a year.
Despite its much publicised Roll Back Malaria Partnership, the World Health Organisation has had limited success in 20 years. The only real impact the programme has had on the disease is through the introduction of insecticide-treated nets (ITNs), which are an effective prophylactic, particularly for children, when used correctly (but which remain heavily taxed in much of Africa).
Most of the world's millions of malaria sufferers are still not benefiting from life-saving drugs nearly five years after the WHO urged their widespread use. Since 2001, the UN health agency has recommended countries switch to artemisinin-based combination drugs (or ACTs) to treat malaria, which has become resistant to conventional medicines, like chloroquine.
The majority of sufferers understand very little about the disease or how it is transmitted (by the female mosquito, which must be pregnant, and which only bites between dusk and dawn).
Ronald Ross, a British doctor born in India, discovered it was the mosquito that transmitted malaria. Until then the popular theory was that foul-smelling gases emitted from swampy soils caused the disease – the word 'malaria' comes from the Italian, 'bad air'. The mortality rate at the time – over a million deaths a year – was reduced to less than 10,000 during the 1950s as a direct result of education and the eradication schemes initiated by Ross. Since the 60s, though, the disease has been on the increase – in 1960 only 10% of the world's population was at risk; that figure now stands at over 40%.
Today, as a result of poor vector control, global warming and intercontinental travel, malaria infects one in 10 of the world's population. It is present in over 100 countries (including eastern Europe, Russia and Turkey), visited by more than 125 million tourists every year, up to 30,000 of whom fall ill when they get home. Last year 1,754 Britons contracted malaria abroad – 1,300 of them the deadliest strain, Plasmodium falciparum (or cerebral malaria). Eleven of them died.
Poverty and poor education compound the problem of malaria in third-world countries, elevating mortality rates. Astonishingly, ignorance of the disease – despite the press coverage it receives and the access to world-class medicine – is a factor in first-world infection, too. Most British travellers who were infected with malaria last year admitted to failing to take correctly – or at all – oral malarial prophylaxis when visiting areas where the disease is endemic.
An investigation conducted earlier this year in the UK found that travellers who sought advice from alternative health centres (complaining that drugs prescribed by their GPs made them feel nauseous) were being offered 'dangerous' advice on malaria prevention and given unproven homoeopathic remedies. Conventional drugs prescribed by GPs are a combination of chloroquine and proguanil, mefloquine (Lariam), doxycycline and Malarone.
As a resident in Africa, I questioned my own doctor about the efficacy and side effects of these drugs. He dismissed chloroquine and proguanil as almost useless, since the parasite has been shown – in this region anyway – to have developed significant resistance to the combination. Lariam, he said, can cause serious neurological disturbances in as many as one in 10 people. Doxycycline increases photosensitivity, which means patients must be prepared to stay out of the sun. It can also interfere with the potency of oral contraception. Malarone, the most recent anti-malarial to be registered, is considered both effective and relatively easily tolerated, but expensive.
Without exception, all short-term visitors to a malarious area should seek advice from the experts (which include the London School of Hygiene and Tropical Medicine, the WHO and the Health Protection Agency) on malarial prophylaxis beforehand. The situation, however, is more complicated for expatriates living in endemic areas, partly because of the risk associated with long-term use of chemoprophylaxis and partly because there is limited data available on the sustained use of some drugs.
The Health Protection Agency suggests that 'the risk of serious side effects associated with long-term prophylactic use of chloroquine and proguanil is low. However, anyone who has taken chloroquine regularly for over five years and requires further prophylaxis should be screened twice-yearly for early retinal changes'. Even before these changes become apparent, there could be other intolerable side effects: my husband, for example, is unable to take proguanil (Paludrine) as it gives him appallingly bad mouth ulcers, which render him unable to eat.
Research suggests there is no increased risk of serious side effects with long-term use of mefloquine (Larium), assuming a person can tolerate it in the short term. Experience of doxycycline in long-term use is limited, though the available data is reassuring (however, like mefloquine, it must be avoided during pregnancy). In many parts of the world, oral prophylaxis is not a guaranteed form of protection; Plasmodium falciparum is increasingly resistant to various antimalarial drugs (indeed my son was on a chloraquine/proguanil combination when he contracted this particularly virulent strain of the disease). As the WHO warns, no antimalarial prophylactic regimen gives complete protection.
Those travelling to malarious areas for extended periods of time (over six months) – or living there (particularly in the case of women, who may become pregnant, and young children) – need to balance the risk of infection against the benefits and side effects of oral prophylaxis; sometimes taking a pill daily gives a false sense of security and might result in laziness when it comes to other prophylactic measures – sleeping under nets, for example, spraying rooms or burning mosquito coils at night.

http://www.guardian.co.uk/money/2008/mar/19/expat-finance-malaria-prevention