Tag: vaccine

  • Ebola vaccine trial in September

    Ebola vaccine trial in September

    The United States will launch an early-stage trial in September of an experimental vaccine against Ebola, the deadly viral disease that has killed 729 people in the largest outbreak in history.

    The National Institutes of Health has been developing an Ebola vaccine for several years that has had “encouraging results” in primates, says Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases. Fauci said he’s working with the Food and Drug Administration to fast track the vaccine into a phase 1 clinical trial this fall. This type of trial is the earliest study in humans and aims to make sure that drugs are safe and show some efficacy.

    Results from the study should be available by January, Fauci said. If the vaccine proves safe and effective, Fauci said he expects that it could be given to health workers in affected African countries sometime in 2015.

    “We are starting to discuss some deals with pharmaceutical companies to help scale it up, so on an emergency basis, it might be available in 2015 for health workers who are putting themselves at extreme risk,” Fauci said.

    Ebola, which has a fatality rate of up to 90%, has infected more than 1,300 people in West Africa, including a number of health workers, according to the World Health Organisation.

    There are currently no effective treatments or vaccines for Ebola, which causes fever and headache in early stages but can lead to hemorrhaging, liver failure and kidney failure in later stages. But scientists have been working on four or five preventive vaccines that appear effective, said Thomas Geisbert, a professor at the University of Texas Medical Branch in Galveston.

    The only positive development to come from the epidemic is that it’s attracted long-needed attention from drug makers, Fauci said.

    “We have been working on our own Ebola vaccine, but we never could get any buy-in from the companies,” he said.

    For years, pharmaceutical companies have seen little potential for profit in Ebola, because outbreaks are unpredictable and typically small, Geisbert said.

    “It’s not like cancer or heart disease, or even a prevalent infectious disease like malaria,” he said.

    The Food and Drug Administration has made exceptions to its usually stringent rules for drug development when considering treatments for Ebola and other rare and lethal diseases, Geisbert said.

    Developing effective treatments is promising for Ebola. These include a man-made antibody treatment; a promising Canadian drug from Tekmira Pharmaceuticals shown to protect monkeys from Ebola; and a vaccine that can be used both to prevent infection and also treat it.

    “One of our goals is to start combining these treatments, like we do with AIDS medications,” Geisbert said.

    He said there are a number of obstacles to bringing these drugs to the clinic.

    “It’s a very fast-moving disease, and you often don’t have a lot of time to intervene,” Geisbert said. “If someone has full-blown Ebola hemorrhagic virus, there is no drug on the planet that is going to protect them. But in the monkey model, we do have drugs where, if you have an early stage of infection and an early stage of illness, some of them are pretty successful.”

    Developing effective treatments is growing more important by the day, as the West African outbreak grows. In the past, public health officials were able to get control of Ebola outbreaks by quarantining the small, remote towns and villages where they occurred, he said.

    Quarantining large populations in more densely populated cities, where Ebola is now occurring, is far more difficult, Geisbert said.

    The disease is popping up in so many places at once. That makes it harder to concentrate health experts and specialists in one area. “It’s spreading the experts who know how to manage these things pretty thin,” he said.

     

    •Culled from USA Today

     

  • Polio: Fighting  a tough battle

    Polio: Fighting a tough battle

    As preparations begin for the next sub-national Immunisation Plus’ Days (IPDs) using bivalent oral polio vaccine, Oyeyemi Gbenga-Mustapha takes a look at why the vaccine preventable polio is still endemic in Nigeria.

    Nigeria is one of the three countries that is still polio-endemic, it is in this unenviable company with Afghanistan and Pakistan. Of all the three, Nigeria is the reservoir of wild polio virus, it is the only country with ongoing transmission of all three serotypes- wild poliovirus type 1, wild poliovirus type 3 and circulating vaccine- desired polio type 2. The Northern states are the main source of polio infections.

    In 2009, operational improvements in these northern states led to a 90 per cent decline in cases of wild poliovirus type 1 and a 50 per cent decline in overall cases compared with 2008.

    As of last week, Polio Global Eradication Initiative, a monitoring organisation of polio situation in Nigeria, reported that two new cases of wild polio virus 1 have been found in Kano and Taraba states, bringing the total number of wild polio cases for this year to 18. The case from Kano is the most recent case in the country.

    According to medical experts, as long as a single child remains infected, children in all countries are at risk of contracting polio. Failure to eradicate polio from these last remaining strongholds could result in as many as 200, 000 new cases every year within 10 years. Polio has no cure but can be prevented.

    In most countries, the global effort has expanded capacities to tackle other infectious diseases by building effective surveillance and immunization systems.

    A delicate balance

    Polio is a highly infectious disease caused by a virus. It invades the nervous system, and can cause total paralysis in a matter of hours. Initial symptoms are fever, fatigue, headache, vomiting, stiffness in the neck and pain in the limbs. According to the World Health Organisation (WHO), one in 200 infections lead to irreversible paralysis (usually in the legs). Among those paralysed, five per cent to 10 per cent die when their breathing muscles become immobilised.

    According to WHO, globally, Polio cases have decreased by over 99 per cent since 1988, from an estimated 350, 000 cases to 223 reported cases in 2012. The reduction is the result of the global effort to eradicate the disease.

    Nigeria is fighting to end the endemic. However, there are sundry factors militating against the actualisation of this hope.

    The polio eradication programme continue to miss too many children in key geographic areas and population groups due to a mixture of operational and social factors. In 2012, going by data supplied by Polio Global Eradication Initiative, 61 children were paralyzed by polio in the first half of 2012, as opposed to 24 at the same time in 2011. In 2011, more than 95 per cent of all cases occurred in the eight persistently endemic northern states of Borno, Jigawa, Kano, Katsina, Kebbi, Sokoto, Yobe and Zamfara.

    A formerly strong primary health care system in northern Nigeria has been weakened over many years due to incessant polio outbreaks and resistant of a segment of the populace over the safety of the vaccination. This has led to serious gap in the administration of the vaccine and subsequent disruption of campaigns as well as the killing of vaccinators. Now routine immunisation services are either no longer available or irregular; coupled with limited resources for health services and gaps in vaccine storage and distribution.

    According to a nongovernmental organisation, PATH, Northern Nigeria has one of the lowest rates of immunisation coverage in the world. In many parts of the north, barely 10 percent of children receive all of their routine vaccines. Coverage rates for the vaccine against tetanus among women are equally low.

    Misunderstood scheme

    The north is rife with misperception on the effects of the contents of the vaccine on health, especially reproduction. Campaigns have been on in the north that vaccination leads to reduction of productivity, this has been countered at all levels but the impact is still there.

    But in the face of sundry factors including insecurity, especially of Boko Haram, ridding the country of the polio virus can remain a mirage. Conflicts and insecurity do weaken public health systems.

    For instance, attacks on health workers in Kano State have robbed vulnerable populations of basic life-saving health interventions. In the face of these, Nigeria continues to pose a significant risk to surrounding countries. In 2011, polio viruses originating from Nigeria were detected in five countries on West and Central Africa. Despite dozens of vaccination campaigns over the past years, according to Polio Global Eradication Initiative, no more than 65 percent of children have received four or more Oral Polio Vaccine (OPV) doses in Borno, Kano, Sokoto and Yobe states.

    Viruses with genetic evidence of long periods of circulation without detection are still being found, indicating surveillance gaps. Sub national engagement of political leadership remains patchy. Future benefits of polio eradication are immense. Once polio is eradicated, the world can celebrate the delivery of a major global public good that will benefit all, no matter where they live. According to WHO, Economic modelling has found that the eradication of polio would save at least US$ 40 to 50 billion over the next 20 years, mostly in low-income countries. Most importantly, success will mean that no child will ever again suffer the terrible effects of lifelong polio-paralysis.