Last Thursday, U.S. health officials reported that after a full decade of decline, Europe and Africa reported an increase in the number of measles cases in 2010.  Because of concerted immunization efforts in those areas, total cases declined from more than 853,000 in 2000 to nearly 278,000 in 2008, and remained stable in 2009. However, the number increased in 2010 to almost 340,000 — a jump of over 21%.  Worldwide, measles remains a very serious problem, with over 20 million cases and 197,000 deaths each year.  Over half of the cases and deaths are in India and China.

The somewhat alarming rise in the number of cases is felt partly due to an increasing reluctance on the part of many parents to have their children immunized against measles. Indeed, in what most physicians feel is a gross misrepresentation of the dangers, claims of severe reactions, including autism, have been used by some parents as an excuse to forego the measles vaccination for their children. In truth, the incidence of serious side effects is very rare.  Most children experience only mild local discomfort, fever, and rash. 

On the other hand, complications from measles such as ear infections (10%), pneumonia (5%) and brain damage from subacute sclerosing panencephalitis — an inflammation of the brain that can lead to convulsions, and leave the victim deaf or mentally retarded (0.1%) are much more common than unwelcome side effects of the vaccine.  Parents of unimmunized children reap the benefits of having the vast majority of the remaining pediatric population immunized, particularly in the United States.  This “free ride” has its limitations, especially for those traveling abroad

In January, four members of an unimmunized family from Kansas who had recently traveled to an undisclosed location overseas, were diagnosed with measles.  Two other cases in unvaccinated persons were reported in the same community one week later. Measles is very contagious and is characterized by high fever, cough, a runny nose, redness in the eyes and a characteristic pink rash that spreads from the face to the feet.

Health officials worldwide are concerned that the efforts to eradicate measles will be stymied if parents continue to resist having their children immunized. Since the measles vaccine is almost always given in combination with mumps and rubella (German measles), these illnesses are likely to see an increase as well.  Although the incidence of measles remains extremely low in the United States, parents with unprotected children going abroad, particularly to areas where the measles virus remains prevalent, should be aware of the risks involved.

Photo by Gates Foundation.

A multi-year investment of $500 million USD by the Gates Foundation, GlaxoSmithKline and the U.S. government has yielded partial success in the search for a malaria vaccine. A recent report in the Wall Street Journal relays the results of a clinical trial published in the New England Journal of Medicine indicating that three doses of the vaccine can cut the risk of developing malaria in half for African children ages five to seventeen months. Researchers are encouraged to see a vaccine protect against the malaria parasite, but say further work is needed to establish its true efficacy. The Gates Foundation has spent $1.75 billion so far in its quest to eradicate the disease and continues to pursue a parallel approach—a “transmission blocking” vaccine—that is believed to be the key to ultimate success.

The worldwide fight against malaria appears to be gaining ground. According to the World Health Organization, malaria killed 781,000 people in 2009, down 20% from 2000, and an analysis by the University of California, San Francisco indicates that some twenty countries are in the process of eliminating malaria (map below). For those planning to travel to subtropics, The Centers for Disease Control has published an interactive map of malaria risk that is the most detailed and useful I have seen to date.

Once one of the most feared contagious illnesses among college students and the military, the incidence of bacterial meningitis due to the Neisseria meningitidis strain has dropped significantly since the introduction of the Menactra meningitis vaccine (MCV4) in 2005.  The American College Health Association, the Centers for Disease Control and Prevention (CDC) and the American Academy of Pediatrics now strongly recommend that all children under the age of 19 receive the Menactra vaccine according to the following schedule:

• 11 to 15 year-olds should be vaccinated routinely with a booster dose given at 16-18 years of age.
• Those 15 years old and higher receiving the vaccine for the first time do not need a booster dose.

Bacterial meningitis may also be caused by other bacterial strains such as Haemophilis and Pneumococcus.  The Haemophilis vaccine (Hib), which has been available for over thirty years and is routinely given to infants, confers reasonable protection against this form of meningitis, while the efficacy of the pneumococcal vaccine (PCV7) in preventing meningitis is less clear. 

Nonetheless, the untimely death of two study abroad students last week is a sober reminder that bacterial meningitis still occurs. Symptoms of bacterial meningitis include fever, severe headache, neck stiffness, nausea and vomiting, rash, and in severe cases confusion and seizures.  The diagnosis is made by examining fluid removed from the spinal canal (spinal tap), while early treatment with the appropriate intravenous antibiotics is essential to avoid long term sequela or death.  Anyone who is experiencing any combination of these symptoms should seek medical care immediately, and anyone who has not received the HIB and Menactra vaccines according to the recommended schedule (including boosters), should make sure these immunizations are made current prior to travel. 

Bacterial meningitis is spread by kissing, sharing utensils and drinking glasses, living in close quarters such as a dormitory or summer camp, and smoking or being exposed to smoke. Being run down, stressed and/or fatigued also increases the risk of infection.  Although not as contagious as the common cold, the mechanism of spread is similar.  Those who have been exposed, and are not properly immunized, may need prophylactic antibiotics such as rifampin or ciprofloxacin after consultation with a medical professional.

Meningitis may also be caused by viruses and other pathogens such as fungi, protozoa and tuberculosis.  Viral meningitis is common, but the symptoms are not as severe and usually require only supportive treatment.  Viral meningitis rarely has any long term effects.   Other types of meningitis are much less common and generally attack only those who are immunocompromised by AIDs or chemotherapy. 

Although there are certain parts of the world, such as the “meningitis belt” of sub Saharan Africa, where bacterial strains that can cause meningitis are commonly found, no part of our planet is free from risk.  HTH Worldwide encourages all travelers to make sure they are properly immunized against bacterial meningitis, and to seek medical help immediately for suspicious symptoms or for known exposure to someone who has been diagnosed with bacterial meningitis.

Each year in mid winter, the World Health Organization (WHO) selects the influenza strains that will be used to develop the vaccine for the following flu season.  The viruses are chosen based on which viruses are prevalent, how they are spreading, and how well the previous season’s vaccine might protect against any that have been newly identified.

This year the WHO Vaccine Composition Committee has picked the same virus strains that were used to develop the influenza vaccine for 2010-2011.  Consequently, the seasonal vaccine for the 2011-2012 season provides protection against the (H1N1)-like virus (swine flu), the (H3N2)-like virus, and the B/Brisbane/60/2008-like virus.

The WHO decision does not mean that those who received the vaccine last year should not be immunized again. Immunity to influenza viruses declines over time and may be too low to provide protection after a year has passed.

Travelers should note that the flu vaccine does not protect against Avian flu, as recent reports of deaths from the Avian flu in Cambodia  remind us. Mortality rates as high as 85% for the Avian flu have been reported in Southeast Asia this year, and only two antiviral medications oseltamavir (Tamiflu®) and zanamavir (Relenza) are useful for H5N1 avian influenza.  The more widely used antivirals, amantadine and rimantidine, are of no help.  Avoiding direct contact with poultry in this region affords the only real protection against the H5N1 flu strain. 

For the latest on flu outbreaks around the world, Travelers should turn to the WHO’s Global Alert and Response Network.

Photo by Sanofi Pasteur.

Yesterday, the Practical Traveler reminded travelers that “Getting vaccinated may be the last thing on your mind when heading off on vacation, but it’s important — whether you are traveling to an exotic destination or not.” This point is illustrated by last month’s advisory from the Centers for Disease Control and Prevention (CDC) documenting the unusually high number of measles cases in the U.S.  Measles has also been a problem in many countries across the globe this year. As we reported in April, the Health Protection Agency in Europe (HPA) has been urging parents to get their children vaccinated against the disease.

Before traveling abroad, check with your doctor or other qualified physician to make sure you (and any family members traveling with you) are caught up on routine immunizations, including tetanus, and find out if there are any vaccines recommended specifically for your destination.  

Photo by gruntzooki.

The Centers for Disease Control and Prevention (CDC) has announced that the 2012 edition of its definitive Yellow Book is now available in bookstores. This authoritative reference work is written by health professionals but is very accessible for international travelers who want to understand the risks of infectious disease around the world and how to manage common problems such as traveler’s diarrhea. The Yellow Book is reissued every two years. The 2012 edition includes these new features:

• Updated maps on the distribution of dengue fever
• More detailed maps for yellow fever and malaria
• Preventing traveler’s diarrhea by understanding how food is prepared
• Tips for traveling to mass gatherings such as the Hajj pilgrimage, the Olympics or the World Cup
• Preparing for study abroad
• How to manage when you are traveling during an international disease outbreak
• In-depth discussions of itineraries that take you to the Caribbean, Egypt, Central America, Mexico and South Africa.

It’s now available through Amazon for $33.43 and soon the ebook version will be available, perfect for the traveler who wants to view it on their Kindle or iPad.

As if budget woes are not enough, last month the State of California officially declared a statewide whooping cough epidemic.  With recorded cases 400 percent higher than last year, including almost 1000 cases in 2010 with five infant deaths, state officials now believe that California is headed for the highest incidence of  pertussis, commonly known as whooping cough, in over 50 years.

California is not alone. The CDC notes that the number of reported cases in the United States tripled between 2002 and 2004.  Although still a far cry from the 175,000 annual cases diagnosed prior to the introduction of the vaccine, the incidence of whooping cough reported annually in the last decade still represents an alarming increase from the less than 3,000 yearly cases in the 1980s.

The dramatic rise in whooping cough is not limited to the United States.  The World Health Organization estimates there were over 17.6 million cases of whooping cough and 300,000 deaths last year alone, making this easily preventable disease one of the world’s leading causes of illness and death. The greatest increase has been in wealthier countries with widespread immunization programs.  The rarity of the illness, coupled with concerns about side effects of the vaccine and the use of vaccines with poor efficacy (Canada, Sweden), has led to an increase in the number of inadequately immunized, or unimmunized children, in developed countries.  In addition, the whooping cough vaccine does not confer lifelong immunity, which means that adults immunized in childhood are susceptible to the illness.  Indeed, almost 25% of whooping cough cases in Europe and the United States are now reported in adults.

Whooping cough is seldom more than a mild inconvenience in those over 10, who may experience prolonged upper respiratory symptoms (runny nose, fever, persistent unproductive cough), but rarely have more serious consequences. Nonetheless, the presence of the B. pertussis infection in adolescents and adults who may transmit the bacteria to infants has led healthcare providers to promote booster immunizations after childhood.  However, booster shots have been approved for adults in only a handful of countries (Canada, France, Germany and the United States), which means that there remains a tremendous reservoir of unprotected adults around the globe, even in developed countries. To compound matters further, there is newly emerging evidence that some strains of the bacteria that cause whooping cough have developed resistance to the newer (acellular) version of the vaccine

Fortunately, the CDC now recommends that anyone traveling outside of the United States receive the DTaP (which includes pertussis protection) vaccine prior to travel. Some resistance notwithstanding, compliance should minimize the risk of contracting the illness overseas and passing it on to susceptible infants who tend to suffer more devastating clinical consequences.

Key West, FL has reported 28 cases of dengue fever since July 2009 – prior to July 2009 dengue was absent from the continental U.S. since 1945 and from Florida since 1934. Why dengue has returned to Florida is still being investigated but some contributing factors might be an increase in mosquitoes capable of delivering the disease, an increase in international travel to areas where dengue fever is more common (Key West is, after all, a Caribbean destination — see below), and the popularity of south Florida as a vacation destination.

Travelers headed to Africa, the South Pacific, Central and South America, the Caribbean and Middle East are reminded to take precautions to guard against the mosquito while traveling.  According to the Centers for Disease Control (CDC), a high number of cases of dengue fever, are being reported from the following areas:
Africa
Cape Verde, Senegal, and the Indian Ocean islands of Mayotte and Reunion

South Pacific
Malaysia, Philippines, Singapore, Sri Lanka, Vietnam and the northern parts of Queensland, Australia

Central and South America and the Caribbean
Argentina, Brazil, Colombia, Costa Rica, Dominican Republic, El Salvador, French Guiana, Guadeloupe, Honduras, Peru and Puerto Rico

Middle East
Jeddah (Saudi Arabia)

Meanwhile,the polio outbreak in Tajikistan seems to be spreading to the borders it shares with Uzbekistan.   An additional 261 cases have been reported since our post in early May.  The CDC is reminding travelers headed to these areas to talk to their doctors regarding the necessary vaccinations for children and those previously vaccinated. 

When traveling into any area affected by an outbreak, be smart, protect yourself however you can, and practice good hygiene.

A British doctor, whose research linked autism to common vaccines, was stripped of his license to practice medicine earlier this week.  Dr. Andrew Wakefield, whose reports in 1998 found an increased incidence of autism in children who received the measles, mumps and rubella vaccines, and whose study influenced millions of parents to forego vaccinations for their children, was found to have conducted “unethical research.” 

In banning him from practicing medicine in the United Kingdom, Britain’s General Medical Council cited a January ruling that “Wakefield and two other doctors acted unethically and showed a callous disregard for the children in their study.”  Among other indiscretions, Wakefield allegedly paid children for blood samples collected at his son’s birthday party and later joked about the incident.

Despite the fact that numerous other studies failed to corroborate Dr. Wakefield’s results, and that the British journal Lancet eventually retracted the original article detailing his findings, vaccination rates in Britain and other rich countries remain lower than before the study was published over a dozen years ago.  This has led to a number of measles outbreaks in Europe each year and even sporadic cases in the United States. 

Dr. Wakefield has appeared as an expert witness in a number of lawsuits against governments and vaccine manufacturers claiming that the measles, mumps and rubella vaccines led to autism.  Over 5,500 claims have been filed attempting to indict the MMR vaccine, but most have been dismissed for lack of evidence.  Two rulings in March of last year by a special branch of the U.S. Court of Federal Claims found no link between vaccines and autism.

In addition, at least a dozen British medical associations including the Royal College of Physicians, the Medical Research Council and the Wellcome Trust have issued statements verifying the safety of the measles, mumps and rubella vaccine. 

Parents of children who did not receive recommended vaccinations as infants should be aware of the dangers of travelling outside of the United States, and of having close contact with other unvaccinated children who have travelled internationally.  In 2008, a 7 year old unvaccinated boy became infected with measles while traveling in Switzerland.  He unknowingly exposed over 800 people and infected 11 unvaccinated children when he returned to California.  The public health cost for managing the outbreak was almost $200,000!

If you have read this far, I hope you have concluded that the answer to this post’s title is: MYTH.  Were you swayed in the past by these false claims?  How about friends or family members?  Let us know if your opinion on this subject has changed over time and why.  It is important to spread facts and not fiction, at least that’s what we here at the Healthy Travel Blog think.

Photo by firma.

Good news for travelers throughout Asia.  There is a new vaccine against Japanese encephalitis that significantly reduces typical side effects.

We all know that mosquitoes transmit some very serious viruses to humans. In addition to malaria and dengue fever, another mosquito-driven disease is Japanese encephalitis virus (JEV).  As reported by the World Health Organization (WHO) JEV is endemic in parts of China, India, the Republic of Korea, Japan, the Russian Federation, islands in the Torres Strait of Australia, Nepal, Thailand, Viet Nam, Cambodia, the Lao People’s Democratic Republic, the Philippines, Taiwan, Indonesia, Malaysia, and Sri Lanka. Its breakouts are generally most prevalent during the summer and fall.

There is no treatment available for this disease which can lead to permanent damage to the nervous system or death. Though many vacationers or expats will not find themselves in high-risk areas during peak times, it is recommended by the Centers for Disease Control (CDC) that anyone travelling to an endemic area during a possible transmission season or those who are headed toward a potentially dangerous area should be vaccinated for JEV.

Historically, the vaccine was toxic to some people — especially those with a history of allergy to wasp/bee stings.  Many doctors were hesitant to give the traditional vaccine and if they did, they would advise recipients to stay in a country with decent medical facilities in case they were one of the rare cases to develop an allergic reaction within 10 days of receiving the vaccine.  Fortunately for those over 18 years of age, there is now a new vaccine that does not cause those side-effects and can be given as safely as any of our other vaccines.

In summary: If you are over 18 years old and travelling to one of the high risk areas mentioned above, ask your doctor for the new non-allergic Japanese encephalitis vaccine.

Author: Charlie Easmon, MBBS
Charlie Easmon, MBBS is a General Practitioner whose practice has a strong focus on Travel Medicine.  He is a Regional Physician Advisor for HTH Worldwide and the Medical Director for The Number One Health Group on Harley Street in London and ALC Global Health Insurance.  He is a member of the Royal College of Physicians, UK and has a Diploma in Tropical Medicine and Hygiene from the University of Liverpool.   Dr. Easmon is an Honorary Lecturer at the London School of Hygiene and Tropical Medicine.