Harman Kardon Of Onkyo

vaccine-preventable diseases: why the Italian travelers are most affected?

's young, male, VFR (Visiting Friends and Relatives), directed in South-Central Asia, born or resident in Italy or in Japan: this hypothetical traveler, if it existed, would bring together all the factors that increase the risk of acquiring a vaccine-preventable disease as a result of an international journey.

It 's the picture that emerges from the GeoSentinel surveillance system, based on a network of 49 clinics spread of tropical diseases in six continents. We analyzed data on passenger care clinics in the network the decade 1997-2007. The findings are reported in an article published in the issue of Vaccine of 28 October.

What diseases?

The most frequent diagnosis was that of enteric fever: under that name were considered together with typhoid fever and paratyphoid, although for the latter there is no specific vaccine. The authors have included paratyphoid (which in the analysis accounted for 32% of cases of enteric fever) because there is some evidence that the live attenuated Ty21a oral typhoid vaccine provides partial protection against Salmonella paratyphi B.

In second place we have hepatitis A. Following influenza, hepatitis B, varicella, measles, whooping cough, bacterial meningitis, rubella, mumps, tick-borne encephalitis, cholera, meningococcal sepsis, anger. There have been no diagnosed cases of yellow fever, Japanese encephalitis and poliomyelitis. There were three deaths, one for rabies, typhoid fever and pneumococcal meningitis.

What travelers?

have been identified, the independent risk factors: young age, male gender, VFR (Visiting Friends and Relatives), South-Central Asia destination. These data had already emerged in previous studies. In particular, VFR travelers, or immigrants in Western countries (and their children born in West) in the country of origin who return to visit relatives and friends, according to data in the literature are at increased risk of various diseases of the traveler, such as vaccine-preventable and malaria.

To be born or to be resident in Italy or Japan was a predictor of the acquisition of a vaccine-preventable disease. The authors offer no interpretation of the data and write broadly that it could be linked to national vaccination policies. Personally, the simplest explanation seems to me that the Italians are in sixth place in the world in terms of international travel but have not yet used to it, rather rooted in other Western countries, to go to a Travel Medicine clinic before leaving. In some parts of Italy, especially in small towns, a service of this type is not even provided by local health authorities, or is not valued in terms of resources, staff training and accessibility to the citizen. The lack of information produces insufficient access to important preventive measures like vaccination or chemoprophylaxis of malaria. As a result, the traveler is not prepared to get sick more often.

What areas of the world?

In (Freely accessible via the following link: http://www.istm.org/Documents/GeoS_Vaccine.pdf ) a very interesting graph is shown in Figure 2.

x-axis are the number of cases per 1000 passengers, on the y axis in the region of the world where the disease was contracted. The colors inside the columns refer to individual diseases.

The region with increased morbidity among travelers is the north-central Asia, mainly due to enteric fever.

In second place (who would have guessed?) Are Eastern Europe, which weighs mainly hepatitis A. Below are other areas of the world, the last place we the sub-Saharan Africa.

The authors do not comment on these results, which to me seem really interesting. One can venture a possible explanation for some unexpected differences in morbidity geographical area: the traveler direct sub-Saharan Africa is probably more inclined to inquire, and then to be vaccinated, compared to a traveler to Europe of 'east, perceived as a low risk area. In addition, malaria tablets Yellow fever vaccination, it must request to enter into certain African sub-Saharan Africa or in transit from one country to another, could serve as drivers for the other vaccinations.

Limitations of the study

Among the limitations of the study highlighted by the authors, the main I think the lack of information on the vaccination status of patients : the only 's previous medical history, the trip included in the surveillance system GeoSentinel, concerning the presence or absence of advice from a clinic of Travel Medicine. Of the reported cases, only 29% of the total and 5% of the VFR had carried out consultancy.

anamnesis In the absence of vaccination, it is not possible to calculate the rate of vaccine failure. Some of those who contracted enteric fever may have been vaccinated. Both the oral vaccine (Ty21a) and parenteral (Vi polysaccharide) are not extremely effective due S. typhi is the estimated efficacy of 63-71%, respectively, for the first and 55-74% for the second, while the oral vaccine may be only partially effective (49%) to S. B. paratyphi

Another limitation to note is that the cohort analyzed is represented only by those who went to one of the clinics in the network GeoSentinel, so that the conclusions of the study can not be automatically extended to the population of travelers in its entirety.

What this study tells us

is an analysis based on data from 580 patients who contracted a vaccine-preventable disease (a total of 37,542 passengers in ammalatisi result of a trip) in a span of ten years, this is the largest study reported to date on the subject. The study provides data that can have a significant relapse practice in consulting that we provide for passengers and can help set priorities for about the recommended vaccinations. As for our country , the results suggest the need to strengthen the activities of Travel Medicine and better information for Italian travelers.

to write this post I am based on the following article:

Andrea K. Boggild, Francesco Castelli, Philippe Gautret, Joseph Torresi, Frank von Sonnenburg, Elizabeth D. Barnett, Christina A. Greenaway, Poh-Lian Lim, Eli Schwartz, Annelies Wilder-Smith, Mary E. Wilson and for the GeoSentinel Surveillance Network.

Vaccine preventable diseases in international returned travelers: Results from the GeoSentinel Surveillance Network. Vaccine 2010, 28:7389-7395

doi: 10.1016/j.vaccine.2010.09.009

To those who wish to learn more about the network GeoSentinel, reports the official site:

http://www.istm.org/geosentinel/main.html

Blood In Cervical Mucus Just Before Period

A new vaccine against serogroup W135-AC-Y meningococcal

International Distribution of serogroups of Neisseria meningitidis prevalent

Source:

Committee to Advise on Tropical Medicine and Travel (CATMAT).

Statement on Meningococcal Vaccination for Travellers. Canada Communicable Disease Report

2009 Volume 35 - ACS-4

http://www.phac-aspc.gc.ca/publicat/ccdr-rmtc/09pdf/acs -dcc-04.pdf

know

13 serogroups of Neisseria meningitidis, identified on the basis of capsular polysaccharide

. Of these, five serogroups (A, B, C, W135 and Y) cause most cases of meningococcal disease

globally.

invasive disease by N. meningitidis (meningitis and sepsis) can occur sporadically or in the form of

outbreaks. The map inserted at the beginning of this post shows the

international distribution of serogroups.

An increased risk of invasive disease by N. meningitidis was observed among individuals who are on their

called meningitis belt (sub-Saharan Africa), where outbreaks

are frequent during the dry season (which extends from December to June) due to both

of environmental factors that may affect the integrity of the upper respiratory tract (

very dry climate, cold nights), both factors social (overcrowding in housing and population movements

linked to socio-cultural or religious reasons) (1). These factors may encourage the movement of N.

meningitidis.

Outside the meningitis belt, the pilgrimage to Mecca (Hajj) is associated with a

increased risk of meningococcal disease: why the government of Saudi Arabia requires pilgrims

a certificate of vaccination meningococcal (2).

outbreaks are regularly reported in other parts of the world, including the Indian subcontinent

and other areas of Asia (3).

For developed countries, it is interesting evolution of the serogroups in the United States:

serogroup Y was responsible for only 2% of all cases in 1989-1991 but later in the mid- 90s, this proportion began to increase. In 2009 (information) serogroup Y became predominant (37%), while the remaining serogroups were as follows: B (32%), C (28%), W135 and other minor (4%) (4).

Until now, travelers who went in at-risk areas could be immunized with a

unconjugated polysaccharide vaccine containing serogroups AC-W135-Y. As with all

unconjugated polysaccharide vaccines, the immunogenicity is not optimal, there is also

induction of immune memory, is not prevented the carrier state, there is induction of herd immunity and can be determined hyporesponsive following repeated administration over time.

has recently been registered in Europe and the United States, and is also available in Italy, a new conjugate vaccine

protein C. diphtheriae CRM197, containing serogroups

AC-W135-Y (5.6).

Clinical trials conducted on this new vaccine have evaluated the immune response in adults and adolescents for each serogroup by measuring the production of antibodies specific anticapsulari, with bactericidal activity (serum bactericidal activity, SBA).

In both adults and adolescents has detected a significantly higher immune response compared to that determined by comparison of non-conjugated polysaccharide vaccine.

The vaccine is administered as a single dose, starting from 11 years of age. Has not been established

need of reminders.

The safety of the vaccine was evaluated in five RCTs with 6185 participants aged between 11 and 65. Among the most common side effects were noted local reactions (erythema, induration, itching, pain at the injection site), and general information such as nausea and headache, lasting 1-2 days.

What advantages and what problems has this new vaccine?

Benefits

are those related to conjugation with a carrier protein: induction of immunological memory

, continued protection, booster effect after a new contact with the antigen

(because, for the presence of the carrier protein, it is T-dependent antigen), decreased

carrier state, induction of herd immunity and no appearance of hyporesponsive after

doses after the first. The incident is typical of the hyporesponsive

conjugate vaccines: There is evidence that subjects who received one dose of meningococcal vaccine

unmarried show a lower immune response to subsequent doses

of the same vaccine in some studies this effect is manifested even when, in subjects previously

immunized with the unconjugated vaccine, revaccination was carried

with a meningococcal conjugate vaccine (7).

Problems

a) the vaccine is registered for use since the 11 years of age. The passenger under the age of 11 years

at the time should be vaccinated with the corresponding product

unmarried. It 's interesting, however, that the Green Book UK

permits the use of off-label even conjugate vaccine in children under one year. This position

Health UK is set out in an updated chapter on meningococcal

added in July 2010 (8);

b) currently is an expensive product (retail price 88 Euro), but this

disadvantage is offset by the fact that is administered in a single dose, while the vaccine

unmarried should be repeated after 3-5 years. For pilgrims to Mecca, unfortunately

now the Saudi government does not distinguish between old and new vaccine, so

continues to restrict the validity of 3 years of vaccination (9) and this represents, together with the high cost

, a limitation to its use in this category of travelers.

should mention that, due to its characteristics, it is not a vaccine for

exclusively for travelers: it can be used in vaccination programs

universal in Western countries even if it occurs, or is deemed possible , an increase in cases of illness

from serogroups A, Y, W135, as happened in the United States. It can also be used

subjects at increased risk for meningococcal disease, such as the

asplenia or patients suffering from deficiency of complement factors.

Bibliografia

(1) WHO. Meningococcal meningitis. Wkly Epidemiol Rec 2003;78:285–96 Available at: http://www.who.int/wer/2003/en/wer7833.pdf

(2) Lingappa JR, Al-Rabeah AM, Hajjeh R, Mustafa T, Fatani A, Al- Bassam T, et al.

Serogroup W-135 meningococcal disease during the Hajj, 2000. Emerg Infect Dis 2003;9:665–71.

(3) Harrison LH, Trotter CL, Ramsay ME. Global epidemiology of meningococcal disease.

Vaccine 2009;27(S2):B51-B63 doi: 10.1016/j.vaccine.2009.04.063

(4) Active Bacterial Core Surveillance (ABCs) Emerging Infections Program Network.

ABCs Report: Neisseria meningitidis, provisional-2009 [Access 23.10.2010]

http://www.cdc.gov/abcs/reports-findings/survreports/mening09.html

(5) European Medicines Agency. Menveo. Summary of product characteristics

http://www.ema.europa.eu/docs/it_IT/document_library/EPAR_-_Product_Information/human/001095/WC500090147.pdf

(6) Licensure of a Meningococcal Conjugate Vaccine (Menveo) and Guidance for Use ---

Advisory Committee on Immunization Practices (ACIP), Morbidity and Mortality Weekly Report

(MMWR) March 12, 2010 / 59(09);273  

http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5909a5.htm

(7) Bröker M and Veitch K. Quadrivalent meningococcal vaccines: Hyporesponsiveness as an important consideration when choosing between the use of conjugate vaccine or polysaccharide vaccine. Travel Medicine and Infectious Diseases 2009;8:47-50

doi:10.1016/j.tmaid.2009.12.001

(8) Immunisation against infectious disease - The Green Book. Updates to Chapter 22:

Meningococcal, 28 July 2010 http://www.dh.gov.uk/prod_consum_dh/groups/dh_digitalassets/@dh/@en/documents/digitalasset/dh_117986.pdf

(9) Kingdom of Saudi Arabia. Ministry of Hajj. Saudi Ministry of Health Requirements.

http://www.hajinformation.com/main/p3001.htm   [Access 23.10.2010]