Solved by verified expert:Research Literature reviews on Determination means (who and where)-in the US-Globally-Prevalent in the north and south (are there more cases in d South or North?)Distribution-Season (when is it common)-Are men and women affected equally?-what is d gender distribution-age distribution-Racial distribution-Social distributionFactors that determine exposure (Risk factors)-Genetic factors-environmental factor-socio-economic factorImpacts on public (effects)-Social effect-the psychological effect-Family effect-Community effect-Economic effectAll these must be accompanied by facts and figures. No Wkipedia pleaseMust be 100% plagiarism freeAttached are some articles, you can add moreThanks
factsheet_lyme_borreliosis_europe.pdf
geographic_distribution_and_expansion_of_human_lyme_disease__united_states___volume_21__number_8___aug.pdf
lyme_disease_facts_and_statistics___bay_area_lyme_foundation.pdf
Unformatted Attachment Preview
Lyme borreLiosis
in europe
This information leaflet
contains five sections
and is intended for a
generic and public health
audience:
© ECDC/G. Hendrickx
1.Lb is found in certain
areas of europe.
What are the risks in
European countries?
2. Ticks can be the
carriers of disease.
How is the disease
transmitted? What are
the risk factors?
3. Disease characteristics
of Lb.
What are the symptoms
and how can it be
treated?
4. Tick-borne diseases
are preventable.
What measures can be
taken to protect
yourself?
5. more information is
available.
Where can you find
more information and
guidance on effective
prevention and control
activities?
Key messages
• Lyme disease, or Lyme borreliosis (LB), is a bacterial disease transmitted to
humans through the bite of infected ticks. It is a common disease in Europe.
• The number of cases in Europe has increased steadily, more than 360 000
cases having been reported over the last two decades.
• Central Europe is the region with the highest incidence of LB, as reported by
the Czech Republic, Estonia, Lithuania and Slovenia.
• The risk of LB is reduced by avoiding tick bites.
• The most effective ways of avoiding tick bites include wearing long trousers and
long-sleeved shirts, and using repellents on the skin and clothing. The skin
should be checked periodically for attached ticks, which should be removed as
soon as possible.
• Typical symptoms include a characteristic skin rash, called erythema migrans,
often accompanied by fever, headache and fatigue. Without antibiotic
treatment, the infection can spread to the joints, the heart and the nervous
system.
• Most cases can be treated successfully with antibiotics taken over several
weeks.
1. Lb is found in certain areas of europe
box 1. What is a vector-borne disease?
LB is the most common tick-borne disease in Europe (Fig. 1).
Between 1990 and 2010, the highest average incidence
rates among the reporting countries were found in Belarus,
Belgium, Croatia, Norway, the Russian Federation and Serbia
(< 5/100 000), Bulgaria, Finland, Hungary, Poland and
© ECDC/G. Hendrickx
• Vector-borne diseases are illnesses caused by pathogens in
human populations.
• These diseases are spread by vectors: living organisms that
can transmit pathogens between humans or from animals
to humans.
• Many vectors are bloodsucking insects, which ingest
pathogens during a blood meal from infected hosts (humans
or animals) and transfer them to new hosts during
subsequent blood meals.
• Mosquitoes are the best known disease vectors. Others
include certain species of ticks, flies, sandflies, and fleas.
Slovakia (< 16/100 000), the Czech Republic, Estonia, and
Lithuania (< 36/100 000) and Slovenia (< 130/100 000).
It is important to be aware of LB risk areas and, if exposure
is likely, to take precautions to reduce the risk of infection.
Fig. 1. Number of Lyme disease cases in europe as reported to WHo Centralized information system for infectious Diseases (CisiD).
2. Ticks can be the carriers of disease
LB is caused by the bacterium, Borrelia burgdorferi, and is
transmitted to humans by the bite of infected ticks, mainly
Ixodes ricinus. Ticks become infected when they feed on
small mammals (such as rodents) and certain birds that
carry the bacterium in their blood. In risk areas, as much as
5-40% of ticks may be infected.
The risk of contracting a tick-borne infection is determined
by the overall number of ticks in the area, the proportion of
those carrying disease, and human behaviour. In risk areas,
people involved in outdoor recreational or occupational
activities (e.g. hunting, fishing, camping, collecting mushrooms
and berries, forestry, farming, military training) are at an
increased risk of being bitten by ticks.
Changes in the geographic and temporal distribution of the
ticks and the disease have been observed in recent
decades. Ticks are spreading to higher altitudes and more
northern latitudes and disease incidence is shifting
towards spring and autumn.
Many factors are involved, including climate change,
changes in land cover and land use, changes in the
distribution of tick hosts, and human-induced changes in the
environment.
3. Disease characteristics of Lb
LB is a multisystem disorder, which can affect several
tissues. The symptoms can be divided according to the two
stages of the disease (early and late) but progress from the
early to the late stage does not always occur. When a person
is bitten by an infected tick, the only symptom in the first
stage consists of a red skin rash or lesion (called erythema
migrans) that spreads in ring form from the site of the bite.
This occurs in about 60–90% of cases within 2–30 days of
the tick bite. If left untreated, a disseminated infection
affecting the nervous system (10% of cases), the joints, the
skin and/or the heart (rare) may follow within days or weeks.
Fig. 2. An example of erythema migrans caused by Lb infection.
No laboratory tests are required to diagnose erythema
migrans (the rash characteristic of LB); a clinical evaluation
and an assessment of the risk of tick exposure suffice.
Laboratory tests are necessary to confirm a diagnosis of latestage infection. B. burgdorferi antibodies are usually
detectable within 4–8 weeks of infection: patients with latestage infection usually test very strongly positive for these
antibodies. However, the occurrence of false-positive tests
in patients with other infections or conditions, such as
autoimmune diseases, can lead to misdiagnosis and
inappropriate treatment.
© CDC/James Gathany
All LB patients should be treated for several weeks with
appropriate antibiotics (amoxicillin, cephalosporin, and
macrolides for disseminated infections). Early treatment can
prevent the risk of developing late-stage complications.
Patients with late-stage LB can also benefit from antibiotics
but if severe tissue damage occurs prior to treatment,
complete recovery may not be possible.
4. Tick-borne diseases are preventable
No licensed vaccine is currently available for LB.
LB infection is best prevented by avoiding tick bites and
promptly removing ticks attached to the skin. An integrated
approach to voiding tick bites and preventing infection is
necessary. This includes wearing protective clothing, using
tick repellents, checking the entire body daily for ticks, and
removing attached ticks before transmission of infection can
occur.
© WHO
Ixodes ticks live on the ground and climb 20-70 cm onto
grasses and bushes where they wait for hosts. The tick bite
is painless and it is often impossible to sense a tick moving
on the skin. An attached tick should be removed using
tweezers or fine-pointed forceps, grasping it as closely as
possible to where it is attached to the skin and pulling it
gently upwards, trying not to break off the mouth parts. The
risk of LB infection is not increased if the mouth parts are
left behind. A skin disinfectant should be applied after
removal of the tick to prevent infection.
When checking the skin for ticks, particular attention should
be paid to skin folds as ticks seek the more humid parts of
the body, such as the groins, the armpits, the waistband
area, under the breasts and behind the knees. In young
children, the head (including the scalp) and the neck area
should also be checked carefully as tick bites are relatively
more common at these sites in this age group. Before
entering homes, clothing, bags and other belongings should
be examined thoroughly for ticks.
The best ways to avoid tick bites are to:
• avoid tick risk areas;
• be informed about how to remove ticks and recognize early
symptoms;
• use insect repellent on skin and clothing when in risk
areas;
• wear protective clothing with long sleeves, and long
trousers tucked into socks or boots.
5. more information is available
WHo documents
Lindgren E, Jaenson TGT. Lyme borreliosis in Europe: influences of climate and climate change, epidemiology, ecology
and adaptation measures. Copenhagen: World Health Organization; 2006
(http://www.euro.who.int/__data/assets/pdf_file/0006/96819/E89522.pdf).
Lyme Borreliosis (Lyme disease). In: International travel and health [website]. Geneva: World Health Organization; 2014
(http://www.who.int/ith/diseases/lyme/en/).
eCDC resources
ECDC communication toolkit on tick-borne diseases. Stockholm: European Centre for Disease Prevention and Control;
(http://www.ecdc.europa.eu/en/healthtopics/emerging_and_vector-borne_diseases/tick_borne_diseases/public_
health_measures/pages/communication_toolkit.aspx).
Factsheet for health professionals – Lyme borreliosis [website]. Stockholm: European Centre for Disease Prevention and
Control; 2010
(http://www.ecdc.europa.eu/en/healthtopics/emerging_and_vector-borne_diseases/tick_borne_diseases/lyme_
disease/factsheet-health-professionals/Pages/factsheet_health_professionals.aspx).
Ixodes ricinus [website]. Stockholm: European Centre for Disease Prevention and Control; 2014
(http://www.ecdc.europa.eu/en/healthtopics/vectors/ticks/Pages/ixodes-ricinus.aspx).
Tick species – distribution maps. In: Tick maps [website]. Stockholm: European Centre for Disease Prevention and
Control; 2010
(http://www.ecdc.europa.eu/en/healthtopics/vectors/vector-maps/Pages/VBORNET-maps-tick-species.aspx).
other resources
Medlock JM et al. Driving forces for changes in geographical distribution of Ixodes ricinus ticks in Europe. Parasites &
Vectors. 2013;6:1
(http://www.parasitesandvectors.com/content/6/1/1).
Randolph SE. Tick ecology: processes and patterns behind the epidemiological risk posed by ixodid ticks as vectors.
Parasitology. 2004;129(S):37-65.
Rizzoli A et al. Lyme borreliosis in Europe. Eurosurveillance. 2011;16(27)
(http://www.eurosurveillance.org/images/dynamic/EE/V16N27/art19906.pdf).
Study Group for Lyme Borreliosis – ESGBOR [website]. Basel: European Society of Clinical Microbiology and Infectious
Diseases; 2013
(https://www.escmid.org/research_projects/study_groups/esgbor/ or http://www.eucalb.com/).
Vázquez M et al. Effectiveness of personal protective measures to prevent Lyme borreliosis. Emerging Infectious
Diseases. 2008;14:210-216.
Lyme borreLiosis in europe
WHO Regional Office for Europe
UN City, Marmorvej 51
DK-2100 Copenhagen Ø, Denmark
http://www.euro.who.int
European Centre for Disease Prevention and Control (ECDC)
Postal address: ECDC, 171 83 Stockholm, Sweden
Visiting address: Tomtebodavägen 11a, Solna, Sweden
http://www.ecdc.europa.eu
Emerging Infectious Disease journal ISSN: 1080-6059
Volume 21, Number 8—August 2015
Dispatch
Geographic Distribution and Expansion of Human Lyme Disease,
United States
On This Page
The Study
Conclusions
Cite This Article
Figures
Figure (/eid/article/21/8/14-1878-f1)
Tables
Table (/eid/article/21/8/14-1878-t1)
Downloads
PDF
RIS
[507 KB - 3 pgs] (/eid/article/21/8/pdfs/14-1878.pdf)
[TXT - 2 KB] (/eid/article/21/8/14-1878.ris)
Altmetric
(https://www.altmetric.com/details.php?domain=wwwnc.cdc.gov&citation_id=4660127)
Kiersten J. Kugeler (/eid/article/21/8/14-1878_article#comment) , Grace M. Farley, Joseph
D. Forrester, and Paul S. Mead
Author affiliations: Centers for Disease Control and Prevention, Fort Collins, Colorado, USA
Cite This Article (javascript:void(0);)
Close (javascript:void(0);)
Highlight and copy the desired format.
Kugeler KJ, Farley GM, Forrester JD, Mead PS. Geographic Distribution and Expansion of
EID Human Lyme Disease, United States. Emerg Infect Dis. 2015;21(8):1455-1457.
https://dx.doi.org/10.3201/eid2108.141878
Kugeler KJ, Farley GM, Forrester JD, et al. Geographic Distribution and Expansion of Human
AMA Lyme Disease, United States. Emerging Infectious Diseases. 2015;21(8):1455-1457.
doi:10.3201/eid2108.141878.
Kugeler, K. J., Farley, G. M., Forrester, J. D., & Mead, P. S. (2015). Geographic Distribution and
APA Expansion of Human Lyme Disease, United States. Emerging Infectious Diseases, 21(8), 14551457. https://dx.doi.org/10.3201/eid2108.141878.
Abstract
Lyme disease occurs in specific geographic regions of the United States. We present a method for
defining high-risk counties based on observed versus expected number of reported human Lyme
disease cases. Applying this method to successive periods shows substantial geographic expansion of
counties at high risk for Lyme disease.
Lyme disease is a multisystem tickborne zoonosis caused by infection with the spirochete Borrelia
burgdorferi (1 ,2 ). Since 1991, state and territorial health departments have reported human Lyme
disease cases to the Centers for Disease Control and Prevention through the National Notifiable Diseases
Surveillance System. Most cases are reported from the northeastern, mid-Atlantic, and north-central
states, although the number of jurisdictions that report a high number of cases has increased over time (3 ).
To better quantify and track the geographic distribution of human Lyme disease, we developed a simple
but robust method for defining counties where residents have a high risk of acquiring this disease.
The Study
Counties with a high incidence of Lyme disease were identified by using SaTScan version 9.1.1(4 ).
Numbers of confirmed Lyme disease cases reported at the county level during 1993–2012 were
aggregated into 5-year intervals (1993–1997, 1998–2002, 2003–2007, 2008–2012) to minimize the
influence of travel-associated cases and short-term changes in surveillance practices. Incidence was
calculated by using each county’s average population at risk, which was estimated from US Census data for
the midpoint of each period (i.e., 1995, 2000, 2005, and 2010). Identification of high-risk clusters was
based on county incidence rates, with a maximum possible cluster size equal to 25% of the US population
(minimum size was 1 county). County centroids were used as geographic reference for analyses. During
the study period, 3 different surveillance case definitions were used (i.e., those established in 1991, 1996,
and 2008) (5 ).
Relative risk (RR) was defined as the observed number of cases divided by the expected number of cases
for a specific period and population size, and adjusted for differences in the population at risk across space
(4 ). Calculations were based on a discrete Poisson probability distribution. RR was calculated for potential
clusters and for individual counties within detected clusters. Statistical significance of possible clusters
was determined by using likelihood ratio tests and standard Monte Carlo hypothesis testing (n = 999
replications) (4 ).
Because of the circular shape used in spatial scanning, not all counties within an identified high-risk cluster
were necessarily characterized by high Lyme disease incidence. Some may have been included because
they share a border with a county having high incidence. Ultimately, counties designated as high incidence
were those within a defined, statistically significant high-risk spatial cluster (α = 0.05) and with a countyspecific RR >2.0.
Figure
Figure (/eid/article/21/8/14-1878-f1). United States counties with high incidence of Lyme disease
by the period when they first met the designated high-incidence criteria, 1993–2012. Highincidence counties were defined as those within a spatial cluster…
In each period, 2 major foci of largely contiguous counties met the high-incidence county designation: 1 in
the northeastern United States and 1 in the north-central United States (Figure). During the first 5-year
period (1993–1997), 69 counties were characterized as having high incidence of Lyme disease, including 4
isolated counties in the southeastern United States (Table (/eid/article/21/8/14-1878-t1); Figure). During
the next period (1998–2002), 130 counties were characterized as having high incidence, and the 4
counties in the southeastern United States ceased to meet the criteria for this designation. During the
third and fourth periods (2003–2007 and 2008–2012), 197 and 260 counties, respectively, were
characterized as having high incidence (Table (/eid/article/21/8/14-1878-t1); Figure).
Over time, the number of counties in the northeastern states identified as having high incidence of Lyme
disease increased >320%: from 43 (1993–1997) to 90 (1998–2002) to 130 (2003–2007) to 182 (2008–
2012). In the north-central states for the same periods, the number of counties having high incidence
increased ≈250%, from 22 to 40 to 67 to 78. In each of the latter periods, a small number of counties
previously identified as having high incidence ceased to meet the criteria; however, most remained above
the threshold during all periods assessed (Table (/eid/article/21/8/14-1878-t1)).
The county geographic center of each major focus was calculated according to Euclidean distances
between county centroids by using ArcGIS 9.3 (Environmental Systems Research Institute, Redlands, CA,
USA). The center of the high-incidence focus in the northeastern United States generally moved westward
and northward, away from the coast of northern New Jersey and into east-central Pennsylvania. In the
north-central high-incidence focus, the geographic center remained relatively stable in northwestern
Wisconsin, moving northward and southward between adjacent counties over time.
∠ Top (javascript:void(0))
∠ Top (javascript:void(0))
Conclusions
We describe a simple measure for objectively defining counties having high incidence of Lyme disease.
Systematic application of this method to 4 consecutive periods showed geographic expansion of high-risk
areas. Despite the substantial increase in the number of counties with high incidence, the limited
movement of the geographic centers suggests relatively constant rates of geographic expansion in all
accessible directions.
Although risk maps for Lyme disease have been developed on the basis of entomologic measures such as
density of and infection prevalence in nymphal Ixodes scapularis vector ticks, these measures do not
uniformly predict risk of human Lyme disease (6 ,7 ). Prior analyses of temporal trends in human Lyme
disease surveillance have not been explicitly spatial or have been conducted by using data from a single
state (8 –13 ).
Surveillance data are subject to several limitations, including changing surveillance case definitions,
availability of public health resources for surveillance, variations in surveillance practices, and reporting
based on county of residence instead of county of exposure. Nevertheless, in accordance with the purpose
of public health surveillance, these data provide valuable information about the magnitude and geographic
distribution of areas in the United States where residents are at high risk of acquiring Lyme disease (5 ,14 ).
Four counties in the southeastern United States had high incidence of human Lyme disease during the
early years of national surveillance but subsequently had low incidence. This circumstance may reflect
improved standardization of diagnostic procedures and a recognition that another condition, southern
tick-associated rash illness (also known as STARI), occurs in the region. Patients with this illness have rash
similar to that of Lyme disease, but the condition is not caused by B. burgdorferi bacteria ( 15 ). The ability
to identify these isolated counties shows that our method is not biased toward detecting only counties
near other areas with high incidence of Lyme disease.
A true reduction in human risk for Lyme disease or changes in surveillance practices may have influenced
the small number of counties meeting high-risk criteria during 1 period but not in subsequent periods. The
RR cutoff of 2.0 was arbitrarily chosen to capture counties with not just elevated risk but a substantially
higher risk for disease than other counties. The overall pattern of expansion in each period was similar
when RR cutoffs of 1.5 and 3.0 were used (data not shown). However, using different RR thresholds to
define …
Purchase answer to see full
attachment
