Epidemic Focus Research Articles

Description of a new epidemic focus of cutaneous Leishmaniasis major in western Burkina Faso

Introductionau Burkina Faso, le seul foyer de leishmaniose cutanée (LC) avec confirmation biologique dans la littérature à notre connaissance est celui de Ouagadougou au centre. Nous rapportons les résultats épidémiologiques, cliniques et biologiques de l’investigation d’un nouveau foyer épidémique à Larama, à l’ouest du Burkina.Méthodesla méthode du camp a été utilisée pour recevoir les cas. Les données sociodémographiques et cliniques ont été recueillies à l’aide d’un questionnaire. La confirmation a été faite par la microscopie puis par réaction en chaîne par polymérase (PCR).Résultatsau total, 108 cas suspects ont été recensés à Larama, soit un taux d’attaque de 5,8%. Le sex ratio était de 1,08. Les patients concernés étaient le plus souvent des cultivateurs (35,2%) et des commerçants (33,3%). La population active (15 à 49 ans) représentait 51,9%. Le nombre de lésion variait entre 1 et 5 dans 91,7% des cas. Les lésions qui se présentaient sous formes ulcéro-crouteuses surélevées et infiltrées, étaient localisées sur les membres (87%) avec une durée d’évolution entre un et cinq mois dans 96,3% des cas. Sur les deux cas prélevés, la microscopie a montré des leishmanies et la PCR a confirmé l’espèce Leishmania major.Conclusionnos résultats confirment l’existence d’une épidémie de leishmaniose cutanée à L. major dans l’ouest du pays. Des enquêtes complémentaires sont nécessaires pour préciser la charge de morbidité des leishmanioses au Burkina Faso.

COVID-19: towards controlling of a pandemic

During the past 3 weeks, new major epidemic foci of coronavirus disease 2019 (COVID-19), some without traceable origin, have been identified and are rapidly expanding in Europe, North America, Asia, and the Middle East, with the first confirmed cases being identified in African and Latin American countries. By March 16, 2020, the number of cases of COVID-19 outside China had increased drastically and the number of affected countries, states, or territories reporting infections to WHO was 143.1 On the basis of ”alarming levels of spread and severity, and by the alarming levels of inaction”, on March 11, 2020, the Director-General of WHO characterised the COVID-19 situation as a pandemic.

Challenges and countermeasures on Chinese malaria elimination programme during the coronavirus disease 2019 (COVID-19) outbreak

Since the end of 2019, the coronavirus disease 2019 (COVID-19) has been extensively epidemic in China, which not only seriously threatens the safety and health of Chinese people, but also challenges the management of other infectious diseases. Currently, there are still approximately three thousand malaria cases imported into China every year. If the diagnosis and treatment of malaria cases as well as the investigation and response of the epidemic foci are not carried out timely, it may endanger patients'lives and cause the possible of secondary transmission, which threatens the achievements of malaria elimination in China. Due to the extensive spread and high transmission ability of the COVID-19, there is a possibility of virus infections among malaria cases during the medical care-seeking behaviors and among healthcare professionals during clinical diagnosis and treatment, sample collection and testing and epidemiological surveys. This paper analyzes the challenges of the COVID-19 for Chinese malaria elimination programme, and proposes the countermeasures in response to the COVID-19 outbreak, so as to provide the reference for healthcare professionals.

Upper respiratory tract infection with new COVID-19 coronavirus infection and aspects of occupational pathology examination

The article discusses the issues of a new coronovirus infection CAVID-19, which suddenly appeared from the end of January 2020. in China and actively, widely spread around the world. The SARS-CoV virus is assigned to group II pathogenicity. The entrance gate of the pathogen is the epithelium of the VDP and epithelial cells of the stomach and intestines. The main source of infection is a sick person who transmits SARS-CoV-2 by airborne droplets and contact. There is a high risk of developing epidemic foci CAVID-19 in medical institutions in case of violation of sanitary and anti-epidemic regime and the risk of epidemic foci in groups of organizations with non-compliance with infection prevention measures. On the basis of the Decree of the President of the Russian Federation dated may 06. 2020 №313 of the Ministry of health of the Russian Federation, together with the FSS and Rospotrebnadzor, additional insurance guarantees are provided to doctors, middle and Junior medical personnel of medical organizations, drivers of ambulances who work directly with patients who have confirmed the presence of a new coronavirus infection (COVID-19). Insurance cases, when a one-time insurance payment is made, are persistent loss of working capacity by a medical worker as a result of complications after a previous illness caused by a new coronavirus infection (COVID-19), confirmed by laboratory research methods, if the disease occurred during the performance of their work duties.

Host diversity of SARS-CoV-2 and primary epidemic focus tracing to COVID-19

There has been a constant debate between the public and academia, what are the natural or intermediate hosts of SARS-CoV-2, and where is the first source of COVID-19 caused by SARS-CoV-2 virus. So far, there is no scientific conclusion yet. With the help of peer-reviewed scientific papers and some well-known preprint scientific reports, this study systematically reviewed the possible host sources of SARS-CoV-2 and traced the source of COVID-19 primary epidemic focus, trying to restore some scientific basis for the occurrence and development of COVID-19, and provide theoretical basis for effective prevention and control.

Anthrax in Dagestan: clinical and epidemiological characteristics, risks, and prognosis of a group outbreak in 2019

Anthrax continues to pose a serious problem for the healthcare and agricultural industries of Russia. Since 1900, over 70,000 outbreaks of human and animal infection have been recorded in Russia. Despite ongoing anti-epidemic measures, epizootics and epidemic foci of anthrax are recorded annually. Over the past 10 years, 23 anthrax outbreaks among people have been recorded in the Russian Federation with a morbidity rate of 90 people, and three fatal outcomes were observed. The Caucasus region ranks first in the Russian Federation in the incidence of anthrax in people and animals. The Republic of Dagestan is a region that is highly prone to anthrax. The spread is aggravated by landscape and environmental conditions that are favorable to the formation and long-term existence of anthrax foci. In most cases, the disease arises in areas previously considered safe for this infection, which indicates the presence of unregistered animal burial sites and the lack of proper control over sanitary condition. People become infected with anthrax due to the uncontrolled and forced farm slaughter of sick animals resulting from the lack of facilities for sanitary slaughter. Human infection occurs mainly during the slaughter of sick cattle, carving, and contact with animal raw materials. This article illustrates a group of anthrax outbreaks that occurred as a result of contact with a sick animal during slaughter and carving. Four local residents of one village fell ill, and in all of them, anthrax manifested in the form of a moderate skin course. The last case of anthrax in cattle in the said locality was recorded in 1958. This fact highlights the importance of compliance with anti-epidemic measures, including the so-called settlements that are safe for anthrax.

Spatially Adjusted Time-varying Reproductive Numbers: Understanding the Geographical Expansion of Urban Dengue Outbreaks

The basic reproductive number (R0) is a fundamental measure used to quantify the transmission potential of an epidemic in public health practice. However, R0 cannot reflect the time-varying nature of an epidemic. A time-varying effective reproductive number Rt can provide more information because it tracks the subsequent evolution of transmission. However, since it neglects individual-level geographical variations in exposure risk, Rt may smooth out interpersonal heterogeneous transmission potential, obscure high-risk spreaders, and hence hamper the effectiveness of control measures in spatial dimension. Therefore, this study proposes a new method for quantifying spatially adjusted (time-varying) reproductive numbers that reflects spatial heterogeneity in transmission potential among individuals. This new method estimates individual-level effective reproductive numbers (Rj) and a summarized indicator for population-level time-varying reproductive number (Rt). Data from the five most severe dengue outbreaks in southern Taiwan from 1998–2015 were used to demonstrate the ability of the method to highlight early spreaders contributing to the geographic expansion of dengue transmission. Our results show spatial heterogeneity in the transmission potential of dengue among individuals and identify the spreaders with the highest Rj during the epidemic period. The results also reveal that super-spreaders are usually early spreaders that locate at the edges of the epidemic foci, which means that these cases could be the drivers of the expansion of the outbreak. Therefore, our proposed method depicts a more detailed spatial-temporal dengue transmission process and identifies the significant role of the edges of the epidemic foci, which could be weak spots in disease control and prevention.

First detection of the kdr mutation (L1014F) in the plague vector Xenopsylla cheopis (Siphonaptera: Pulicidae)

BackgroundThe oriental rat flea, Xenopsylla cheopis, is the most efficient vector of the plague. Pyrethroid insecticides such as cypermethrin, cyhalothrin and deltamethrin have been often used to limit plague transmission via controlling the vector during outbreaks. However, this strategy is threatened by the development of insecticide resistance. Understanding the mechanisms underlying pyrethroid resistance is the prerequisite for successful flea control.MethodsPartial DNA sequences of X. cheopis voltage gated sodium channel (VGSC) gene were amplified from a total of 111 individuals, collected from a natural plague epidemic foci in Baise City, Guangxi Zhuang Autonomous Region of China. These DNA fragments were sequenced. The frequency and distribution of kdr mutations were assessed in four X. cheopis populations. The origin of kdr mutations was investigated by phylogenetic and network analysis.ResultsThe classical knockdown resistance (kdr) mutation (L1014F) was detected in four field populations at frequencies ranging between 0.021–0.241. The mutant homozygote was observed only in one of the four populations. Seven haplotypes were identified, with two of them carrying the resistance L1014F mutation. Phylogenetic tree and network analysis indicated that the L1014F allele was not singly originated. Based on polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) profiling, an easy-to-use and accurate molecular assay for screening individual fleas for the L1014F mutation was developed.ConclusionsTo our knowledge, this work represents the first report of the L1014F mutation in the plague vector X. cheopis. The incidence of the L1014F allele highlights the need of further studies on the phenotypic effect of this mutation in this plague vector. Early detection and monitoring of insecticide resistance is suggested in order to make effective control strategies in case of plague outbreaks in this region.

Cientific substantiation of sizes of sanitary protection zones of anthrax burial sites based on the comprehensive evaluation of risk factors

In the Russian Federation anthrax epizootics are still being registered among animals as well as epidemic foci of the population. This situation is linked to natural reservoirs of the pathogen - numerous anthrax burial sites which belong to class I of dangerous objects. In this connection, a one-kilometer sanitary protective zone is required according to current Russian Federation legislation. As a result, a significant land of the country is unsuitable for any agricultural use. Meanwhile, epizootologo-epidemiological observations indicate to that different anthrax burial sites differ in their characteristics and represent varying degrees of the risk. In connection with the development of the agricultural sector, intensive construction and the development of new and abandoned areas there is a need of creating unified approaches to assess the risk of anthrax burial sites, as well as to determine the size of sanitary protection zones based on the risk assessment. This article represents an original methodology to assess the actual danger of anthrax burial sites. It is based on a comprehensive multi-factor quantity-related risk assessment, described by a model that accounting the importance of each study for natural, social and biological factors. Undertaking this methodology allowed to reveal a degree of danger of anthrax burial sites located in different territories of the Russian Federation, and helped to substantiate the dimensions of their sanitary protection zones.

Clinical and epidemiological patterns of chickenpox in adults in the Primorsky territory

Objective: to establish clinical and epidemiological patterns of chickenpox in adults in the Primorsky Territory to improve treatment and prevention work. Materials and methods: The study used statistics on the incidence of chicken pox in the Primorsky Territory from 2009 to 2017 and demographic data on the population for the specified period. A clinical characteristic of 102 cases of varicella in patients hospitalized in the infectious disease ward of Primorsky Regional Clinical Hospital No. 2 (Vladivostok) in 2015-2017 is given. Results: From 2009 to 2017, the incidence of chickenpox in the Primorsky Territory was consistently high, with an average of 636.2 per 100,000 population. Analysis of the structure of patients showed that the maximum proportion of cases of chicken pox occur in organized children 3-6 years old (55.9%), schoolchildren (19.1%) and children 1–2 years old (11.6%). The proportion of 15–17 year olds was 3.0%. Adults, from 18 years old – 4.9%. The proportion of unorganized children 3–6 years old (2.9%) and children in the first year of life (2.6%) is not high. High risk of infection was detected in Vladivostok (57.8 per 100.000), Yakovlevsky (52.1% ooo), Olginsky (45.9% ooo), Lazovsky (42.8% ooo) and Shkotovsky (40, 2% ooo) areas. In the annual dynamics, a pronounced spring-summer seasonal rise was formed. The clinical course of varicella in the group of adults was characterized by an average duration of the initial period of the disease of 1.4 ± 0.7 days. For clinical diagnosis, an important time was the appearance of the rash, which varied within four days. The phenomenon of “spillage” was noted in 97% of patients. The rash was polymorphic, with the formation of crusts. The period of height was characterized by the presence of catarrhal manifestations. The granularity of the posterior pharyngeal wall was observed in all patients without exception. In 84.3% of patients there was a bright hyperemia of the pharynx. In 14.7% of cases, enantema was detected on the soft palate, palatine arches, and posterior pharyngeal wall. Dry cough was detected in 28 of 103 patients, which probably increased their epidemiological significance. Findings: The clinical picture of varicella was typical and was represented by a combination of intoxication, exanthema, and catarrhal syndrome. The epidemic process of varicella in adults in Primorsky Krai was characterized by relative autonomy of manifestations in adults, children up to one year old, and unorganized children. When implementing chickenpox epidemiological surveillance, priority should be given to interventions in epidemic foci.

Characteristics of the Epidemiological Situation of Measles in the Period of its Elimination in Republic of Moldova

Relevance Measles continues to be one of the priorities of health care worldwide, due to it high contagiosity, still widespread, severity of the disease and complications. A high degree of population migration contributes to the spread of infection, i.e. global measles virus circulation, clinical change and late diagnosis, inadequate immunization coverage. Aim. Analysis of measles incidence in the Republic of Moldova in 2000–2018. and features of the epidemic process. Materials and Methods. Statistics on measles incidence and immunization coverage in 2000–2018 were used. 340 cases of measles registered in the country in 2018 were subjected to a detailed analysis Results There is a decrease in measles vaccination coverage, in 2017–87.1%. In the same year, the coverage with the first revaccination at 6–7 years was 92.4% and the second at 14–15 years is 94.9%, which is not enough to maintain epidemiological well-being. There are territorial differences in vaccination coverage. In 2018, imported cases of measles were in 62.5% from Ukraine, 25.0% from Russia and 12.5% from Romania. There have been isolated measles cases (14), and epidemic foci or outbreaks (7), with from 2 to 252 cases of measles. The largest measles outbreak in 2018 was registered among those who rest in a religious camp unvaccinated against measles. The average age of the diseased is 14 years, and in outbreaks with a significant number of cases (9 and more) within 7.9–14.9 years. In the age structure of the diseased, children from 1 to 10 years old prevail (66.1%), children under one year old make up 8,2%, teenagers 17,5% and adults 8.2%. Only 11.0% received one dose of measles vaccine, and 3.6% of the relevant age groups received two doses of vaccine. The reason is the refusal of vaccination for religious motive. In 196 (57.6%) cases, the diagnosis was confirmed by laboratory methods, and in the remaining 144 (42.4%) by clinical and epidemiological data. Conclusions Measles remains a childhood infection, but cases of the disease occur among adolescents (17.5%) and adults (8.2%). The uneven of vaccination coverage throughout the country, the low level of responsibility of the population, the increased incidence of measles in neighboring countries, the high level of population migration are risk factors for the importation and spread of measles.

Spatiotemporal analysis and epidemiological characterization of the human immunodeficiency virus (HIV) in Libya within a twenty five year\xa0 period: 1993\u20132017

BackgroundInfection with the human immunodeficiency virus (HIV) is an alarming problem in North African countries, but few studies have analyzed the geographical distribution of the epidemic. Libya, the second largest country in Africa and with the longest coast on the Mediterranean basin facing Europe, has experienced major outbreaks of HIV infection. Since then, no studies have followed up on the burden of HIV infections. To plan interventions and allocate resources, spatial analysis of HIV/AIDS clusters are required in order to identify epidemic foci and trends in the country. The objective of this study was to assess HIV infection clustering and trends in Libya.MethodsInformation on all recorded HIV/AIDS cases during 1993–2017 were extracted from the National Reporting System. A total of 8015 newly diagnosed HIV cases with address information were included. Spatial autocorrelation and spatial–temporal analysis were used to identify HIV clusters. Spatial correlations between cases and socio-demographic factors were determined using spatial regression.ResultsHIV cases steadily increased within the Libyan population, particularly among those aged < 27 years. Spatiotemporal analysis showed marked geographic and temporal variation of HIV infection, particularly during 2005–2012. The risk factors varied from one region to another, and the contribution of injection drug use to infection increased with time. Four clusters in three time periods were identified, three on the Mediterranean coast and one in the south.ConclusionHIV is an emerging problem in Libya, particularly among young adults. The infection rate varies greatly among the regions and districts, particularly within certain definable geographical areas. Effective intervention strategies are needed to contain HIV infections, especially within the endemic areas.

The characteristics of current natural foci of hemorrhagic fever with renal syndrome in Shandong Province, China, 2012-2015.

BackgroundHemorrhagic fever with renal syndrome (HFRS), an infectious disease caused by hantaviruses, is endemic in China and remains a serious public health problem. Historically, Shandong Province has had the largest HFRS burden in China. However, we do not have a comprehensive and clear understanding of the current epidemic foci of HFRS in Shandong Province.Methodology/principal findingsThe incidence and mortality rates were calculated, and a phylogenetic analysis was performed after laboratory testing of the virus in rodents. Spatial epidemiology analysis was applied to investigate the epidemic foci, including their sources. A total of 6,206 HFRS cases and 59 related deaths were reported in Shandong Province. The virus carriage rates of the rodents Rattus norvegicus, Apodemus agrarius and Mus musculus were 10.24%, 6.31% and 0.27%, respectively. The phylogenetic analysis indicated that two novel viruses obtained from R. norvegicus in Anqiu City and Qingzhou City were dissimilar to the other strains, but closely related to strains previously isolated in northeastern China. Three epidemic foci were defined, two of which were derived from the Jining and Linyi epidemic foci, respectively, while the other was the residue of the Jining epidemic focus.Conclusions/significanceThe southeastern and central Shandong Province are current key HFRS epidemic foci dominated by A. agrarius and R. norvegicus, respectively. Our study could help local departments to strengthen prevention and control measures in key areas to reduce the hazards of HFRS.

MODELING OF NOZOAREL CHANGES AND ZONE OF INCREASED EPIDEMIC RISK OF WEST NILE FEVER IN RUSSIA IN CONNECTION WITH THE EXPECTED CLIMATE CHANGE

In the course of the analysis of the literature, the main climatic parameter was determined that determines the nosoareal of West Nile fever in Russia – the sum of the active temperatures. It has been shown that for intense virus circulation in the warm season, the sum of active temperatures at a threshold of 10°C should be more than 2200°C, at values of more than 2800°C the area is considered epidemic. Based on these criteria, maps of the changes in the nosoareal of West Nile fever under model climate conditions in different periods of the 21st century are constructed. It has been shown that over the 21st century, the nosoareal and the area of increased risk of the development of epidemic foci of West Nile fever will expand to the north and capture new subjects of the Russian Federation.

ORGANIZATION OF PREVENTIVE, ANTI-EPIDEMIC ACTIONS TO DECREASE RISKS OF EPIDEMIC SITUATION COMPLICATIONS FOR PLAGUE IN REPUBLIC ALTAI

Aim - аnalysis and evaluation of efficiency of anti-epidemic, preventive actions for decrease of plague infection risk for the population and prevention of this illness export outside the Republic Altai limits. Analysis was performed by the data of practical and research Establishments of Rospotrebnadzor. Due to occurrence of three epidemic plague foci in local population in Gorno-Altai natural focus where the infection source was an Altai marmot, the complex of organizational, anti-epidemic, preventive actions was performed for its localization and liquidation and also minimization of risk of anthropogenous plague distribution in Republic Altai and its exportation from the endemic region. Interaction of the Services and Departments in realization of organizational, anti-epidemic, preventive actions in Kosh-Agach district created the necessary conditions for localization, liquidation of the epidemic plague foci in the shortest terms, prevented the illness distribution by the anthropogenous way and its exportation outside the limits of the enzootic territory.

FACTORS RESPONSIBLE FOR CLUSTER HFRS MORBIDITY DURING WINTER SEASON IN THE TERRITORY OF THE REPUBLIC OF BASHKORTOSTAN

Aim. Of the study was to specify the factors responsible for outbreaks of domestic cluster HFRS morbidity during winter period in the Republic of Bashkortostan as the basis for preventive measures substantiation. Materials and methods. Analyzed have been the data from the Rospotrebnadzor Administration in the Republic of Bashkortostan (RB) on the HFRS incidence in 54 administrative districts of RB during winter season 2016-2017. Summarized have been the results of epidemic foci eradication with domestic HFRS morbidity during winter months of 2010-2017 in the territory of RB. Results. Winter sporadic HFRS incidence is registered annually among the rural and urban population residing in steppe, forest-steppe and forest zones of RB. It is outlined that epidemic foci with domestic cluster HFRS morbidity emerge more frequently in the territory of forest-steppe zone. It is established that HFRS infections of domestic type take place in residential areas adjacent to some forestry to one extent or another, as well as on visiting country, out-of-town objects situated in the territory of active natural HFRS foci. Thereat, the risks of domestic HFRS infection are entirely defined by the sanitary-hygienic state of accommodation and manufacturing facilities. Conclusion. The main tactical option for the prevention of epidemic foci emergence with domestic cluster HFRS morbidity among rural and urban population of RB is simultaneous barrier and semi-rural deratization and disinfection in areas of high risk of infection.

Surveillance and risk assessment system of schistosomiasis epidemic focus in Hankou marshland of Wuhan City

To construct a monitoring and risk assessment system of schistosomiasis epidemic focus in marshland, so as to grasp the risk of schistosomiasis transmission, and to provide the technical support for targeted prevention and control measures. The crowd and the risk source of schistosomiasis in Hankou marshland in Wuhan City were monitored to grasp the risk factors of schistosomiasis. The risk level was evaluated by the three-dimensional risk matrix and three-dimensional visualization method. The total numbers of people on holidays and working days were 59 582 and 36 382 persontimes a day respectively in Hankou marshland. Fishing and swimming were the most common ways to contact the river water. The most majority of the people exposed to river water were male (73.9%), retirees (36.1%), local residents (69.7%) and people whose income was 1000 - 3000 yuan per month (52.1%), and the awareness of protection of them was low. In spring, the average density of living Oncomelania hupensis snails was 0.993/0.1 m2, the rat density was 7.72%, and the density of wild feces was 0.78/hm2. In autumn, the average density of living snails was 0.596 /0.1 m2, the rat density was 5.22%, and the density of wild feces was 0.32/hm2. The average density of living snails, the rat density and the density of wild feces were reduced by 39.9%, 32.4% and 59.0% respectively in autumn compared with those in spring. The risk assessment results of three-dimensional matrix showed that part 1 and part 2 were medium risk, part 3 was high risk and part 4 was maximum risk. The risk assessment results of the visualization method showed that the risk level increased from part 1 to part 4, which were basically consistent with the results of the risk matrix. There is a relatively large risk of schistosome infection in Hankou marshland in 2013. The surveillance and risk assessment system of epidemic focus is feasible and scientific.

Protecting Privacy in Trajectories with a User-Centric Approach

The increased use of location-aware devices, such as smartphones, generates a large amount of trajectory data. These data can be useful in several domains, like marketing, path modeling, localization of an epidemic focus, and so on. Nevertheless, since trajectory information contains personal mobility data, improper use or publication of trajectory data can threaten users’ privacy. It may reveal sensitive details like habits of behavior, religious beliefs, and sexual preferences. Therefore, many users might be unwilling to share their trajectory data without a previous anonymization process. Currently, several proposals to address this problem can be found in the literature. These solutions focus on anonymizing data before its publication, i.e., when they are already stored in the server database. Nevertheless, we argue that this approach gives the user no control about the information she shares. For this reason, we propose anonymizing data in the users’ mobile devices, before they are sent to a third party. This article extends our previous work which was, to the best of our knowledge, the first one to anonymize data at the client side, allowing users to select the amount and accuracy of shared data. In this article, we describe an improved version of the protocol, and we include the implementation together with an analysis of the results obtained after the simulation with real trajectory data.

High genetic diversity in hard ticks from a China-Myanmar border county

BackgroundMany tick species have great morphological similarity and are thus grouped into species complexes. Molecular methods are therefore useful in the classification and identification of ticks. However, little is known about the genetic diversity of hard ticks in China, especially at the subspecies level. Tengchong is one of the epidemic foci of tick-borne diseases in China, but the tick species inhabiting the local area are still unknown.MethodsEighteen villages in Tengchong County, China, were selected for sampling carried out from September to October 2014. Infesting hard ticks were removed from the body surface of domestic animals and questing ticks were collected from grazing fields. After morphological identification, molecular characteristics of each tick species were analyzed based on both 16S rRNA and cytochrome c oxidase subunit 1 (cox1) gene fragments.ResultsSix tick species were identified based on morphology: Rhipicephalus microplus, R. haemaphysaloides, Ixodes ovatus, Haemaphysalis longicornis, H. shimoga and H. kitaokai. Phylogenetic analysis using the cox1 gene revealed that R. microplus ticks from the present study belong to clade C. For tick samples of both R. haemaphysaloides and I. ovatus, three phylogenetic groups were recognized, and the intergroup genetic distances exceeded the usual tick species boundaries. Haemaphysalis longicornis ticks were clustered into two separate clades based on the cox1 gene. For ticks from both H. shimoga and H. kitaokai, two phylogenetic groups were recognized based on the phylogenetic analysis of the 16S rRNA gene, and the intergroup genetic distances also exceeded the known boundaries for closely related tick species.ConclusionsAccording to molecular analyses, new species or subspecies closely related to R. haemaphysaloides, I. ovatus, H. shimoga and H. kitaokai probably exist in the China-Myanmar border Tengchong County, or these ticks form species complexes with highly divergent mitochondrial lineages. Morphological comparisons are warranted to further confirm the taxonomic status of these tick species.

Progress of malaria elimination of Jiangsu Province, China

There were vivax malaria, falciparum malaria, and malariae malaria epidemic in Jiangsu Province, and vivax malaria was the dominant disease. Anopheles sinensis and An. anthropophagus were malaria-transmitted vectors. Since the founding of People's Republic of China, there have been two major malaria outbreaks in Jiangsu Province, when the highest annual malaria incidence reached up to 24.95%. According to prevention and control principles of "adjusting measures to local conditions, giving different guidance to different categories and highlighting key points", during the epidemic outbreak stage, the largescale malaria prevention and control measures were implemented for all the residents who were target population in Jiangsu malaria-endemic areas. During the basic eradication stage, the targeted prevention and control measures had been carried out according to the different epidemic features to gradually consolidate the achievement of prevention and control in Jiangsu Province. In the malaria elimination stage, Jiangsu Province focused on controlling of the source of infection and malaria surveillance. According to the "1-3-7 targeted elimination" work model, the management of infectious sources and investigation and disposal of foci were carried out for each epidemic focus to block the malaria transmission. By the end of 2017, there had been no indigenous malaria cases for the six consecutive years in Jiangsu Province. All the 13 cities have passed the assessment of malaria elimination of Jiangsu Province. Although Jiangsu Province has achieved the goal of malaria elimination, it is urgent and necessary to maintain and improve malaria surveillance capabilities to prevent malaria reintroduction.