Global & Disaster Medicine

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Italy: 4 cases of locally transmitted P. falciparum malaria

CDC

Malaria Outbreak in Ginosa, Italy

On October 3, 2017, Italy reported four cases of locally transmitted P. falciparum malaria among migrant agricultural workers in Ginosa, which is in the Taranto Province of the Apulia region of Italy. The four patients were males, between 21–37 years of age, and lived in camps with other migrant workers in the Ginosa area. Three of the patients were from Morocco where there is no malaria, and one is from Sudan which is a malaria-endemic country. All reported no travel for the past two months. Italian public health authorities continue to investigate this outbreak.

Italy was declared free of malaria by the World Health Organization in 1970. However, the mosquitoes that transmit malaria, specifically Anopheles labrachiae, An. manulipennis, An. superpictus, and possibly An. sacharovi, are present. Thus, rare autochthonous cases have been reported including P. vivax in Tuscany in 1997 and P. vivax in Latina Province in 2009.

Given the focal, limited nature of this outbreak so far, CDC recommends only mosquito avoidance measures for travelers to agricultural areas of Ginosa. These measures include using insect repellent when outdoors, staying in an air-conditioned or well-screened area, and sleeping under an insecticide-treated bed net. CDC will continue to monitor the malaria situation in Italy and will update these recommendations as needed.

See the CDC malaria website for additional health information about malaria, including prevention of mosquito bites and drugs for malaria prevention. For general health information for travelers to all areas of the world, see the CDC Travelers’ Health website.


After five long years, malaria is back with a vengeance in Delhi and the number of cases has shot up alarmingly to 113

Pioneer

Picture of a woman taking malaria pills

 


WHO: New vector control response seen as game-changer

WHO

The call came from the WHO Director-General in May 2016 for a renewed attack on the global spread of vector-borne diseases.

“What we are seeing now looks more and more like a dramatic resurgence of the threat from emerging and re-emerging infectious diseases,” Dr Margaret Chan told Member States at the Sixty-ninth World Health Assembly. “The world is not prepared to cope.”

Dr Chan noted that the spread of Zika virus disease, the resurgence of dengue, and the emerging threat from chikungunya were the result of weak mosquito control policies from the 1970s. It was during that decade that funding and efforts for vector control were greatly reduced.

‘Vector control has not been a priority’

Dr Ana Carolina Silva Santelli has witnessed this first-hand. As former head of the programme for malaria, dengue, Zika and chikungunya with Brazil’s Ministry of Health, she saw vector-control efforts wane over her 13 years there. Equipment such as spraying machines, supplies such as insecticides and personnel such as entomologists were not replaced as needed. “Vector control has not been a priority,” she said.

Today more than 80% of the world’s population is at risk of vector-borne disease, with half at risk of two or more diseases. Mosquitoes can transmit, among other diseases, malaria, lymphatic filariasis, Japanese encephalitis and West Nile; flies can transmit onchocerciasis, leishmaniasis and human African trypanosomiasis (sleeping sickness); and bugs or ticks can transmit Chagas disease, Lyme disease and encephalitis.

Together, the major vector-borne diseases kill more than 700 000 people each year, with populations in poverty-stricken tropical and subtropical areas at highest risk. Other vector-borne diseases, such as tick-borne encephalitis, are of increasing concern in temperate regions.

Rapid unplanned urbanization, massive increases in international travel and trade, altered agricultural practices and other environmental changes are fuelling the spread of vectors worldwide, putting more and more people at risk. Malnourished people and those with weakened immunity are especially susceptible.

A new approach

Over the past year, WHO has spearheaded a new strategic approach to reprioritize vector control. The Global Malaria Programme and the Department of Control of Neglected Tropical Diseases – along with the Special Programme for Research and Training in Tropical Diseases, have led a broad consultation tapping into the experience of ministries of health and technical experts. The process was steered by a group of eminent scientists and public health experts led by Dr Santelli and Professor Thomas Scott from the Department of Entomology and Nematology at the University of California, Davis and resulted in the Global Vector Control Response (GVCR) 2017–2030.

At its Seventieth session, the World Health Assembly unanimously welcomed the proposed response.

The GVCR outlines key areas of activity that will radically change the control of vector-borne diseases:

  • Aligning action across sectors, since vector control is more than just spraying insecticides or delivering nets. That might mean ministries of health working with city planners to eradicate breeding sites used by mosquitoes;
  • Engaging and mobilizing communities to protect themselves and build resilience against future disease outbreaks;
  • Enhancing surveillance to trigger early responses to increases in disease or vector populations, and to identify when and why interventions are not working as expected; and
  • Scaling-up vector-control tools and using them in combination to maximize impact on disease while minimizing impact on the environment.

Specifically, the new integrated approach calls for national programmes to be realigned so that public health workers can focus on the complete spectrum of relevant vectors and thereby control all of the diseases they cause.

Recognizing that efforts must be adapted to local needs and sustained, the success of the response will depend on the ability of countries to strengthen their vector-control programmes with financial resources and staff.

A call to pursue novel interventions aggressively

The GVCR also calls for the aggressive pursuit of promising novel interventions such as devising new insecticides; creating spatial repellents and odour-baited traps; improving house screening; pursuing development of a common bacterium that stops viruses from replicating inside mosquitoes; and modifying the genes of male mosquitoes so that their offspring die early.

Economic development also brings solutions. “If people lived in houses that had solid floors and windows with screens or air conditioning, they wouldn’t need a bednet,” said Professor Scott. “So, by improving people’s standard of living, we would significantly reduce these diseases.”

An entomologist inserts live mosquitoes in wall of a mud house in Kisumu, Kenya

An entomologist inserts live mosquitoes into a standard ‘cone bioassay’. After 30 minutes he will see how many have been killed – this will measure if the insecticide was sprayed properly on the walls, and constitutes intervention monitoring.
WHO/S. Torfinn

The call for a more coherent and holistic approach to vector control does not diminish the considerable advances made against individual vector-borne diseases.

Malaria is a prime example. Over the past 15 years, its incidence in sub-Saharan Africa has been cut by 45% – primarily due to the massive use of insecticide-treated bed nets and spraying of residual insecticides inside houses.

But that success has had a down side.

“We’ve been so successful, in some ways, with our control that we reduced the number of public health entomologists – the people who can do this stuff well,” said Professor Steve Lindsay, a public health entomologist at Durham University in Britain. “We’re a disappearing breed.”

The GVCR calls for countries to invest in a vector-control workforce trained in public health entomology and empowered in health care responses.

“We now need more nuanced control – not one-size-fits-all, but to tailor control to local conditions,” Professor Lindsay said. This is needed to tackle new and emerging diseases, but also to push towards elimination of others such as malaria, he said.

Dr Lindsay noted that, under the new strategic approach, individual diseases such as Zika, dengue and chikungunya will no longer be considered as separate threats. “What this represents is not three different diseases, but one mosquito – Aedes aegypti,” said Professor Lindsay.

GVCR dovetails with Sustainable Development Goals

The GVCR will also help countries achieve at least 6 of the 17 Sustainable Development Goals. Of direct relevance are goal 3 on good health and well-being, goal 6 on clean water and sanitation, and goal 11 on sustainable cities and communities.

The GVCR goals are ambitious – to reduce mortality from vector-borne diseases by at least 75% and incidence by at least 60% by 2030 – and to prevent epidemics in all countries.

The annual price tag is US$ 330 million globally, or about 5 cents per person – for workforce, coordination and surveillance costs. This is a modest additional investment in relation to insecticide-treated nets, indoor sprays and community-based activities, which usually exceed US$ 1 per person protected per year.

It also represents less than 10% of what is currently spent each year on strategies to control vectors that spread malaria, dengue and Chagas disease alone. Ultimately, the shift in focus to integrated and locally adapted vector control will save money.

‘A call for action’

Dr Santelli expressed optimism that the GVCR will help ministries of health around the world gain support from their governments for a renewed focus on vector control.

“Most of all, this document is a call for action,” said Dr Santelli, who now serves as deputy director for epidemiology in the Brasilia office of the U.S. Centers for Disease Control and Prevention.

It will not be easy, she predicts. The work to integrate vector-control efforts across different diseases will require more equipment, more people and more money as well as a change in mentality. “The risk of inaction is greater,” said Dr Santelli, “given the growing number of emerging disease threats.” The potential impact of the GVCR is immense: to put in place new strategies that will reduce overall burden and, in some places, even eliminate these diseases once and for all.


CDC: Malaria

Each year 1,500 people in the U.S. are diagnosed with Malaria after international travel. www.cdc.gov/globalhealth

About 70% of all malaria deaths worldwide are among children under 5 years old. www.cdc.gov/globalhealth

More than 90% of Malaria deaths are in the Africa region. www.cdc.gov/globalhealth


Serious and fatal bouts of malaria in the United States are a greater problem than has been previously reported

NY Times

The study was published Monday by The American Journal of Tropical Medicine and Hygiene.

The authors counted 22,000 patients hospitalized for malaria, about five times as many as were hospitalized, for example, for dengue fever….. Nearly 5,000 of them had serious complications like kidney failure or coma, and 182 died.

winter travel anopheles

 


The world’s first vaccine against malaria will be introduced in three countries – Ghana, Kenya and Malawi – starting in 2018.

BBC

“….Despite huge progress, there are still 212 million new cases of malaria each year and 429,000 deaths…..”

 


Burundi’s Health minister Dr Josiane Nijimbere: More than 3,700 people have died from the mosquito-borne disease since 2016.

The East African

 


Experimental PfSPZ malaria vaccine provides durable protection against multiple strains in NIH clinical trial  

NIH

Tuesday, February 21, 2017

Experimental PfSPZ malaria vaccine provides durable protection against multiple strains in NIH clinical trial

 

“An effective malaria vaccine will need to protect people living in endemic areas against multiple strains of the mosquito-borne disease.”

Anthony S. Fauci, M.D., Director, NIAID

An investigational malaria vaccine has protected a small number of healthy U.S. adults from infection with a malaria strain different from that contained in the vaccine, according to a study published today in the Proceedings of the National Academy of Sciences (PNAS). The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, sponsored and co-conducted the Phase 1 clinical trial.

Malaria is transmitted to humans through the bite of infected mosquitoes, which inject immature malaria parasites called sporozoites into a person’s bloodstream. The parasites travel to the liver, where they mature, multiply and spread via the bloodstream throughout the body causing malaria symptoms including chills, fever, headache, nausea, sweating and fatigue. According to the World Health Organization, 214 million people were infected with malaria globally in 2015 and 438,000 people died, mostly young African children. The species Plasmodium falciparum is the most common cause of malaria morbidity and mortality in Africa. In the United States, travel-related malaria is a concern for international tourists, aid workers and military personnel worldwide.

The PfSPZ Vaccine used in this study was developed by Sanaria Inc., of Rockville, Maryland. The vaccine contains weakened P. falciparum sporozoites that do not cause infection but are able to generate a protective immune response against live malaria infection. Earlier research at the NIH Clinical Center with the PfSPZ Vaccine found it to be safe, well-tolerated and protective for more than a year when tested in healthy U.S. adults against a single Africa-derived malaria strain matched to the PfSPZ Vaccine.

“An effective malaria vaccine will need to protect people living in endemic areas against multiple strains of the mosquito-borne disease,” said NIAID Director Anthony S. Fauci, M.D. “These new findings showing cross-protection with the PfSPZ Vaccine suggest that it may be able to accomplish this goal.”

The study enrolled 31 healthy adults ages 18 to 45 years, and was led by Julie E. Ledgerwood, D.O. of NIAID’s Vaccine Research Center (VRC), and Kirsten E. Lyke, M.D. of the University of Maryland Center for Vaccine Development in Baltimore. Participants were assigned to receive three doses of the PfSPZ Vaccine at eight-week intervals by rapid intravenous injection.

Nineteen weeks after receiving the final dose of the test vaccine, participants who received the vaccine and a group of non-vaccinated volunteers were exposed in a controlled setting to bites from mosquitoes infected with the same strain of P. falciparum parasites (NF54, from Africa) that were used to manufacture PfSPZ Vaccine.

Nine of the 14 participants (64 percent) who received PfSPZ Vaccine demonstrated no evidence of malaria parasites; all six of the non-vaccinated participants who were challenged at the same time had malaria parasites in their blood.

Of the nine participants who showed no evidence of malaria, six participants were again exposed in a controlled setting to mosquito bites, this time from mosquitoes infected with a different strain of P. falciparum parasite, 33 weeks after the final immunization. In this group, 5 of the 6 participants (83 percent) were protected against malaria infection; none of the six participants who did not receive the vaccine and were challenged were protected. All participants who became infected with malaria immediately received medical treatment.

“Achieving durable protection against a malaria strain different from the vaccine strain, over eight months after vaccination, is an indication of this vaccine’s potential,” said Robert A. Seder, M.D., chief of the Cellular Immunology Section of NIAID’s Vaccine Research Center and senior author of the PNAS paper. “If we can build on these findings with the PfSPZ Vaccine and induce higher efficacy, we may be on our way to a vaccine that could effectively protect people against a variety of malaria parasites where the disease is prevalent.”

The research team found that the PfSPZ Vaccine activated T cells, a key component of the body’s defenses against malaria, and induced antibody responses in all vaccine recipients. Vaccine-specific T-cell responses were comparable when measured against both of the malaria challenge strains, providing some insights into how the vaccine was mediating protection.

Ongoing research will determine whether protective efficacy can be improved by changes to the PfSPZ Vaccine dose and number of immunizations.  Accordingly, a Phase 2 efficacy trial testing three different dosages in a three-dose vaccine regimen is now underway in 5-to 12-month-old infants in Western Kenya to assess safety and efficacy against natural infection.

Sanaria Inc., designed, manufactured, and provided PfSPZ Vaccine and the heterologous challenge mosquitoes. NIAID supported the development of the experimental vaccine through several Small Business Innovation Research grants: 5R44AI055229-11, 5R44AI058499-08, and 5R44AI058375-08. For more information about the Phase 1 study, see clinicaltrials.gov using the identifier: NCT02015091.

NIAID conducts and supports research — at NIH, throughout the United States, and worldwide — to study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID website.

About the National Institutes of Health (NIH): NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.

NIH…Turning Discovery Into Health®

Reference

K. Lyke et al. PfSPZ vaccine induces strain-transcending T cells and durable protection against heterologous controlled human malaria infection. PNAS DOI 10.1073/pnas.1615324114 (2017).


A malaria vaccine was completely successful in preventing the disease in 35 humans

Nature

Sterile protection against human malaria by chemoattenuated PfSPZ vaccine

Nature Year published:(2017)

DOI:doi:10.1038/nature21060

“…..PfSPZ-CVac is a highly efficacious vaccine candidate; when we are able to optimize the immunization regimen (dose, interval between doses, and drug partner), this vaccine could be used for combination mass drug administration and a mass vaccination program approach to eliminate malaria from geographically defined areas……”

 

 


Artemether-lumefantrine: A key malaria treatment has failed for the first time in 4 patients being treated in the UK

BBC


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