Two Decades of Wildlife Pathogen Surveillance: Case Study of Choclo orthohantavirus and Its Wild Reservoir Oligoryzomys costaricensis.

The Costa Rican pygmy rice rat (Oligoryzomys costaricensis) is the primary reservoir of Choclo orthohantavirus (CHOV), the causal agent of hantavirus disease, pulmonary syndrome, and fever in humans in Panama. Since the emergence of CHOV in early 2000, we have systematically sampled and archived rodents from >150 sites across Panama to establish a baseline understanding of the host and virus, producing a permanent archive of holistic specimens that we are now probing in greater detail. We summarize these collections and explore preliminary habitat/virus associations to guide future wildlife surveillance and public health efforts related to CHOV and other zoonotic pathogens. Host sequences of the mitochondrial cytochrome b gene form a single monophyletic clade in Panama, despite wide distribution across Panama. Seropositive samples were concentrated in the central region of western Panama, consistent with the ecology of this agricultural commensal and the higher incidence of CHOV in humans in that region. Hantavirus seroprevalence in the pygmy rice rat was >15% overall, with the highest prevalence in agricultural areas (21%) and the lowest prevalence in shrublands (11%). Host-pathogen distribution, transmission dynamics, genomic evolution, and habitat affinities can be derived from the preserved samples, which include frozen tissues, and now provide a foundation for expanded investigations of orthohantaviruses in Panama.

Hantavirus in Panama: Twenty Years of Epidemiological Surveillance Experience.

Twenty years have passed since the emergence of hantavirus zoonosis in Panama at the beginning of this millennium. We provide an overview of epidemiological surveillance of hantavirus disease (hantavirus pulmonary syndrome and hantavirus fever) during the period 1999-2019 by including all reported and confirmed cases according to the case definition established by the health authority. Our findings reveal that hantavirus disease is a low-frequency disease, affecting primarily young people, with a relatively low case-fatality rate compared to other hantaviruses in the Americas (e.g., ANDV and SNV). It presents an annual variation with peaks every 4-5 years and an interannual variation influenced by agricultural activities. Hantavirus disease is endemic in about 27% of Panama, which corresponds to agroecological conditions that favor the population dynamics of the rodent host, Oligoryzomys costaricensis and the virus (Choclo orthohantavirus) responsible for hantavirus disease. However, this does not rule out the existence of other endemic areas to be characterized. Undoubtedly, decentralization of the laboratory test and dissemination of evidence-based surveillance guidelines and regulations have standardized and improved diagnosis, notification at the level of the primary care system, and management in intensive care units nationwide.

HIV transmitted drug resistance in adult and pediatric populations in Panama.

OBJECTIVE: To investigate the prevalence of transmitted drug-resistant HIV among adults in Panama by using a modified World Health Organization Threshold Survey (WHO-TS) and to investigate rates of initial resistance among HIV-positive infants in Panama. METHODS: At the Gorgas Memorial Institute, 47 HIV-positive adults were genotyped for mutations associated with transmitted drug resistance (TDR) in the reverse transcriptase and protease genes of HIV-1, according to WHO-TS guidelines, modified to include patients ≤ 26 years old. Prevalence rates for drug-resistance mutations against three classes of antiretroviral drugs-nucleoside analog reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), and protease inhibitors-were calculated as low (< 5.0%), moderate (5.0%-15.0%), and high (> 15.0%). Twenty-five infant patients were also geno-typed and prevalence rates for drug-resistance mutations were calculated. RESULTS: TDR among Panamanian adults was moderate: 6 of 47 HIV-positive adults showed one or more mutations associated with TDR. Horizontal TDR mutations were moderate for NRTIs and NNRTIs and low for protease inhibitors. Vertical transmission of HIV in Panama has decreased for 2002-2007, but vertical HIV TDR prevalence is moderate (12.0%) and is emerging as a problem due to incomplete antiretroviral coverage in pregnancy. CONCLUSIONS: The prevalence of HIV TDR indicated by this study, combined with known rates of HIV infection in Panama, suggests more extensive surveys are needed to identify risk factors associated with transmission of HIV drug resistance. Specific WHO-TS guidelines for monitoring vertical transmission of drug-resistant HIV should be established.

Molecular Identification of Parasites Causing Cutaneous Leishmaniasis in Panama.

Isolates from 475 cutaneous leishmaniasis (CL) patients from three endemic regions were studied by three typing techniques. The molecular analysis from lesion scrapings based on hsp70 PCR-restriction fragment length polymorphism (RFLP) showed that 78.1% (371/475) restriction patterns corresponded to Leishmania (Viannia) panamensis, 19% (90/475) to Leishmania (Viannia) guyanensis, and 3.0% (14/475) to Leishmania (Viannia) braziliensis. Promastigotes isolated by culture from lesions of 228 patients (48.0%, 228/475) were identified by multi-locus enzyme electrophoresis. Of them, 95.2% (217/228) were typified as L. (V.) panamensis, 1.3% (3/228) as L. (V.) guyanensis, 2.2% (5/228) as L. (V.) braziliensis, and 1.3% (3/228) as hybrids (L. [V.] braziliensis/L. [V.] panamensis). However, a partial sequencing analysis of the hsp70 gene from 77 selected samples showed 16.9% (13/77) typified as L. (V.) panamensis, 68.8% (53/77) as Leishmania (V.) sp., 1, 3.9% (3/77) as L. (V.) guyanensis, 1.3% (1/77) as L. (V.) braziliensis outlier, 2.6% (2/77) as Leishmania (Viannia) naiffi, 2.6% as (2/77) Leishmania (V.) sp., and 2 and 3.9% (3/77) hybrid isolates of L. (V.) braziliensis/L. (V.) guyanensis. These results confirm L. (V.) panamensis as the predominant species and cause of CL lesions in Panama and that L. (V.) guyanensis, L. (V.) braziliensis, and L. (V.) naiffi are circulating to a lower degree. Furthermore, the determination of parasite isolates belonging to atypical clusters and hybrid isolates suggests the circulation of genetic variants with important implications for the epidemiology and clinical follow-up of CL in Panama. No evidence of the existence of parasites of the Leishmania (Leishmania) mexicana complex in Panamanian territory was found in this study.

Evolutionary history and spatiotemporal dynamics of the HIV-1 subtype B epidemic in Guatemala.

Different explanations exist on how HIV-1 subtype B spread in Central America, but the role of Guatemala, the Central American country with the highest number of people living with the virus, in this scenario is unknown. We investigated the evolutionary history and spatiotemporal dynamics of HIV-1 subtype B in Guatemala. A total of 1,047 HIV-1 subtype B pol sequences, from newly diagnosed ART-naïve, HIV-infected Guatemalan subjects enrolled between 2011 and 2013 were combined with published subtype B sequences from other Central American countries (n = 2,101) and with reference sequences representative of the BPANDEMIC and BCAR lineages from the United States (n = 465), France (n = 344) and the Caribbean (n = 238). Estimates of evolutionary, demographic, and phylogeographic parameters were obtained from sequence data using maximum likelihood and Bayesian coalescent-based methods. The majority of Guatemalan sequences (98.9%) belonged to the BPANDEMIC clade, and 75.2% of these sequences branched within 10 monophyletic clades: four also included sequences from other Central American countries (BCAM-I to BCAM-IV) and six were mostly (>99%) composed by Guatemalan sequences (BGU clades). Most clades mainly comprised sequences from heterosexual individuals. Bayesian coalescent-based analyses suggested that BGU clades originated during the 1990s and 2000s, whereas BCAM clades originated between the late 1970s and mid 1980s. The major hub of dissemination of all BGU, and of BCAM-II, and BCAM-IV clades was traced to the Department of Guatemala, while the root location of BCAM-I and BCAM-III was traced to Honduras. Most Guatemalan clades experienced initial phases of exponential growth (0.23 and 3.6 year-1), followed by recent growth declines. Our observations suggest that the Guatemalan HIV-1 subtype B epidemic is driven by dissemination of multiple BPANDEMIC founder viral strains, some restricted to Guatemala and others widely disseminated in the Central American region, with Guatemala City identified as a major hub of viral dissemination. Our results also suggest the existence of different sub-epidemics within Guatemala for which different targeted prevention efforts might be needed.

HIV-1 Antiretroviral Drug Resistance Mutations in Treatment Naïve and Experienced Panamanian Subjects: Impact on National Use of EFV-Based Schemes.

The use of antiretroviral therapy in HIV infected subjects prevents AIDS-related illness and delayed occurrence of death. In Panama, rollout of ART started in 1999 and national coverage has reached 62.8% since then. The objective of this study was to determine the level and patterns of acquired drug resistance mutations of clinical relevance (ADR-CRM) and surveillance drug resistance mutations (SDRMs) from 717 HIV-1 pol gene sequences obtained from 467 ARV drug-experienced and 250 ARV drug-naïve HIV-1 subtypes B infected subjects during 2007-2013, respectively. The overall prevalence of SDRM and of ADR-CRM during the study period was 9.2% and 87.6%, respectively. The majority of subjects with ADR-CRM had a pattern of mutations that confer resistance to at least two classes of ARV inhibitors. The non-nucleoside reverse transcriptase inhibitor (NNRTI) mutations K103N and P225H were more prevalent in both ARV drug-naïve and ARV drug-experienced subjects. The nucleoside reverse transcriptase inhibitor (NRTI) mutation M184V was more frequent in ARV drug-experienced individuals, while T215YFrev and M41L were more frequent in ARV drug-naïve subjects. Prevalence of mutations associated to protease inhibitors (PI) was lower than 4.1% in both types of subjects. Therefore, there is a high level of resistance (>73%) to Efavirenz/Nevirapine, Lamivudine and Azidothymidine in ARV drug-experienced subjects, and an intermediate to high level of resistance (5-10%) to Efavirenz/Nevirapine in ARV drug-naïve subjects. During the study period, we observed an increasing trend in the prevalence of ADR-CRM in subjects under first-line schemes, but not significant changes in the prevalence of SDRM. These results reinforce the paramount importance of a national surveillance system of ADR-CRM and SDRM for national management policies of subjects living with HIV.

Phylogenetic Analysis of Hepatitis B Virus Genotypes Circulating in Different Risk Groups of Panama, Evidence of the Introduction of Genotype A2 in the Country.

The Hepatitis B Virus (HBV) can cause acute or chronic infection it is also associated with the development of liver cancer, thousands of new infections occur on a yearly basis, and many of these cases are located in certain areas of the Caribbean and Latin America. In these areas, the HBV prevalence is still high which makes this virus a serious public health concern to the entire region. Studies performed in Panama suggest a complex pattern in the distribution of HBV among the country's different risk groups. We use phylogenetic analysis in order to determine which HBV genotypes were circulating in these specific groups; for this we used a fragment of the PreS2/2 region of the HBV genome. Subsequently whole HBV genome sequences were used for Bayesian analysis of phylodynamics and phylogeography. Two main genotypes were found: genotype A (54.5%) and genotype F (45.5%). There was a difference in the distribution of genotypes according to risk groups: 72.9% of high risk groups were associated to genotype A, and 55.0% of samples of genotype F were associated to the low risk group (p<0.002). The Bayesian analysis of phylogeny-traits association revealed a statistically significant geographical association (p<0.0001) with both genotypes and different regions of the country. The Bayesian time of most recent common ancestor analysis (tMRCA) revealed a recent tMRCA for genotype A2 circulating in Panama (1997, 95% HPD: 1986-2005), when it is compared with Panamanian genotype F1c sequences (1930, 95% HPD: 1810 - 2005). These results suggest a possible change in the distribution of HBV genotypes in Panama and Latin America as a whole. They also serve to encourage the implementation of vaccination programs in high-risk groups, in order to prevent an increase in the number of new HBV cases in Latin America and worldwide.

Spatiotemporal dynamics of dissemination of non-pandemic HIV-1 subtype B clades in the Caribbean region.

The Human immunodeficiency virus type-1 (HIV-1) epidemic in the Caribbean region is mostly driven by subtype B; but information about the pattern of viral spread in this geographic region is scarce and different studies point to quite divergent models of viral dissemination. In this study, we reconstructed the spatiotemporal and population dynamics of the HIV-1 subtype B epidemic in the Caribbean. A total of 1,806 HIV-1 subtype B pol sequences collected from 17 different Caribbean islands between 1996 and 2011 were analyzed together with sequences from the United States (n = 525) and France (n = 340) included as control. Maximum Likelihood phylogenetic analyses revealed that HIV-1 subtype B infections in the Caribbean are driven by dissemination of the pandemic clade (BPANDEMIC) responsible for most subtype B infections across the world, and older non-pandemic lineages (BCAR) characteristics of the Caribbean region. The non-pandemic BCAR strains account for >40% of HIV-1 infections in most Caribbean islands; with exception of Cuba and Puerto Rico. Bayesian phylogeographic analyses indicate that BCAR strains probably arose in the island of Hispaniola (Haiti/Dominican Republic) around the middle 1960s and were later disseminated to Trinidad and Tobago and to Jamaica between the late 1960s and the early 1970s. In the following years, the BCAR strains were also disseminated from Hispaniola and Trinidad and Tobago to other Lesser Antilles islands at multiple times. The BCAR clades circulating in Hispaniola, Jamaica and Trinidad and Tobago appear to have experienced an initial phase of exponential growth, with mean estimated growth rates of 0.35-0.45 year(-1), followed by a more recent stabilization since the middle 1990s. These results demonstrate that non-pandemic subtype B lineages have been widely disseminated through the Caribbean since the late 1960s and account for an important fraction of current HIV-1 infections in the region.

High diversity of hepatitis B virus genotypes in Panamanian blood donors: a molecular analysis of new variants.

Hepatitis B Virus (HBV) is an infectious agent that causes more than half of the cases of liver disease and cancer in the world. Globally there are around 250 million people chronically infected with this virus. Despite 16% of the cases of liver disease in Central America are caused by HBV, the information regarding its genetic diversity, genotypes and circulation is scarce. The purpose of this study was to evaluate the genetic variability of the HBV genotypes from HBV-DNA positive samples obtained from screening blood donors at the Social Security System of Panama and to estimate its possible origin. From 59,696 blood donors tested for HBV infection during 2010-2012, there were 74 HBV-DNA positive subjects. Analysis of the partial PreS2-S region of 27 sequences shows that 21% of the infections were caused by genotype A, 3% by genotype D and 76% by genotype F. In addition, we were able to confirm circulation of six sub-genotypes A1, A2, A3, D4, F3, F1 and a proposed new sub-genotype denominated F5pan. We found a confinement of sub-genotypes F1 and F5pan to the western area of Panama. The tMRCA analysis suggests a simultaneous circulation of previously described sub-genotypes rather than recent introductions of the Panamanian sub-genotypes in the country. Moreover, these results highlight the need of more intensive research of the HBV strains circulating in the region at the molecular level. In conclusion, Panama has a high HBV genotype diversity that includes a new proposed sub-genotype, an elevated number of PreCore-Core mutations, and confinement of these variants in a specific geographical location.

Molecular epidemiology of HIV-1 in Panama: origin of non-B subtypes in samples collected from 2007 to 2013.

Phylogenetic studies have suggested that the HIV-1 epidemic in the Americas is mainly dominated by HIV subtype B. However, countries of South America and the Caribbean have recently reported changes in their circulating HIV-1 genetic profiles. The aim of this study was to characterize the molecular profile of the HIV-1 epidemic in Panama by the analysis of 655 polymerase gene (pol) sequences that were obtained from HIV-infected Panamanians diagnosed between 1987 and 2013. Blood samples were collected from recently infected, antiretroviral drug-naïve and treatment-experienced subjects since mid-2007 to 2013. Viral RNA from plasma was extracted and sequences of HIV protease and reverse transcriptase genes were obtained. Bootscanning and phylogenetic methods were used for HIV subtyping and to trace the putative origin of non-B subtype strains. Our results showed that HIV-1 infections in Panama are dominated by subtype B (98.9%). The remaining 1.1% is represented by a diverse collection of recombinant variants including: three URFs_BC, one CRF20_BG, and one CRF28/29_BF, in addition to one subtype F1 and one subtype C, none of which were previously reported in Panama. The non-B subtype variants detected in Panama were probably introduced from Brazil (subtype F1 and CRF28/29_BF), Cuba (CRF20_BG), Dominican Republic (URFs_BC) and India (subtype C). Panama is the geographical vertex that connects the North with South America and the Caribbean through trade and cultural relations, which may explain the observed introductions of non-B subtype HIV-1 variants from both the Caribbean and South America into this Central American country.

Human immunodeficiency virus type 1 (HIV-1) subtype B epidemic in Panama is mainly driven by dissemination of country-specific clades.

The Human immunodeficiency virus type-1 (HIV-1) subtype B is the most predominant clade in Central America; but information about the evolutionary history of this virus in this geographic region is scarce. In this study, we reconstructed the spatiotemporal and population dynamics of the HIV-1 subtype B epidemic in Panama. A total of 761 HIV-1 subtype B pol sequences obtained in Panama between 2004 and 2013 were combined with subtype B pol sequences from the Americas and Europe. Maximum Likelihood phylogenetic analyses revealed that HIV-1 subtype B infections in Panama derived from the dissemination of multiple founder viruses. Most Panamanian subtype B viruses (94.5%) belong to the pandemic viral strain proposed as originated in the US, whereas others (5.5%) were intermixed among non-pandemic Caribbean strains. The bulk (76.6%) of subtype B sequences from Panama grouped within 12 country-specific clades that were not detected in other Central American countries. Bayesian coalescent-based analyses suggest that most Panamanian clades probably originated between the early 1970s and the early 1980s. The root location of major Panamanian clades was traced to the most densely populated districts of Panama province. Major Panamanian clades appear to have experienced one or two periods of exponential growth of variable duration between the 1970s and the 2000s, with median growth rates from 0.2 to 0.4 year(-1). Thus, the HIV-1 subtype B epidemic in Panama is driven by the expansion of local viral strains that were introduced from the Caribbean and other American countries at an early stage of the AIDS pandemic.

Hantavirus fever without pulmonary syndrome in Panama.

In Panama, hantavirus pulmonary syndrome (HPS) is caused by Choclo virus, a species phylogenetically related to Andes and Maporal viruses. Up to 60% of the population has been positive for specific serum antibody in community-based surveys, but mortality is very uncommon. In four western Panama clinics, we tested individuals presenting with a severe febrile prodrome for acute hantavirus (HV) infection by immunoglobulin M enzyme-linked immunosorbent assay and reverse transcription polymerase chain reaction as well as clinically similar infections, such as dengue and leptospirosis. From 2006 to 2009, at least 21% of 117 patients diagnosed with HV infection had HV Fever (HF) with no evidence of pulmonary edema (no respiratory distress or radiographic lung infiltrates), and 44% of patients had very mild HPS (radiographic pulmonary edema but no respiratory insufficiency). HV infection caused by Choclo virus in Panama presents often as HF, which contrasts with HV in the Americas but is consistent with the high seroprevalence in endemic regions.

Molecular diagnosis of echovirus 30 as the etiological agent in an outbreak of aseptic meningitis in Panama: May-June 2008.

INTRODUCTION: Aseptic meningitis outbreaks are commonly caused by viral pathogens with enterovirus a common etiological agent. Between May and June of 2008, an outbreak of 173 cases of aseptic meningitis occurred in the Chiriqui Province of Panama. Molecular techniques were used to identify the etiological agent. METHODOLOGY: Cerebrospinal fluid (CSF) samples from 75 patients were received at the Gorgas Memorial Institute for Health Studies.  RNA extraction and one-step RT-PCR were performed on each sample to determine the presence of enterovirus.  Thirty-four samples which were positive for enterovirus were subject to group-specific PCR, sequencing, and phylogenetic analysis to identify the etiological agent of the outbreak. RESULTS: The CSF of 58 subjects was found positive for the enterovirus family using RT-PCR. Thirty-four samples were found to belong to the enterovirus B group. Phylogenetic analysis of four successfully sequenced samples revealed echovirus 30 as the etiological agent. CONCLUSION: Echovirus 30 is reported as the likely cause of an outbreak of aseptic meningitis in Panama, the first since the 1980s.

Simple, specific molecular typing of dengue virus isolates using one-step RT-PCR and restriction fragment length polymorphism.

A one-step RT-PCR and one-enzyme RFLP was used to detect and distinguish among flaviviruses, including the four serotypes of dengue and the St. Louis Encephalitis, West Nile and Yellow Fever viruses in cultured virus samples or acute-phase human serum. Using a previously described RT-PCR, but novel RFLP procedure, results are obtained in 24 h with basic PCR and electrophoresis equipment. There is 95% agreement between RT-PCR/RFLP results and those achieved by indirect immunofluorescence assays, and 100% agreement between RT-PCR/RFLP results and gene sequencing. This method is more rapid than tests of cytopathic effect based on virus isolation in tissue culture, and simpler than real-time PCR. It does not require specialized equipment, radioisotopes or computer analysis and is a method that can be applied widely in the developing world. It allows for prompt determination of whether a flavivirus is the cause of illness in a febrile patient, rapid identification of dengue serotypes in circulation, and improved patient management in cases where prior dengue exposure make dengue hemorrhagic fever or dengue shock syndrome a risk.

Beginning of personalized medicine in Panama: Molecular and pathological characteristics of gastrointestinal stromal tumors from archival paraffin-embedded tissue.

This is the first study from Central America to analyze genetic mutations and histopathological features associated with gastrointestinal stromal tumors (GIST). Mutations found in the tyrosine kinase membrane receptors c-kit and pdgfra are associated with clinical and pathological characteristics of GIST. New drugs that inhibit the expression of these oncogenes at the molecular level substantially improve the quality of life for patients with this tumor. It is therefore essential for patient care in Panama that genetic analysis of GIST tumors continues to develop from the pilot study presented herein into routine clinical use. This study evaluated 39 cases of GIST in Panama, using samples archived at the Instituto Oncológico Nacional from 1994 to 2004. DNA from paraffin­embedded tumor tissues was isolated and amplified for the exons of c-kit and pdgfra associated with a high frequency of mutations. Direct PCR sequencing of specific exons was performed, and those with different alleles were cloned and re-sequenced. Amino acid sequences were inferred from DNA and aligned to Genbank reference sequences to determine the position and type of mutation. The highest frequency of mutations was found in exon 11 of the c-kit gene (70%). Mutations found in this exon were heterogeneous, while only one type of mutation (p.A502_Y503dup) was observed in c-kit exon 9. Mutations in the pdgfra gene constituted several substitutions, with the deletion p.D842V being observed most frequently. The observed GIST-associated mutations were previously described. Four patients with mutations associated with familial GIST were also found. The majority (66%) of patients with mutations in exon 11 (residues 550-591) were considered to be at high risk and 75% of patients with mutations specifically within residues 556-560 (exon 11) were considered to have high-risk GIST. This is the first molecular study of GIST in Central America. It was performed to gain a better understanding of the cancer-associated mutations of KIT and platelet­derived growth factor receptor α (PDGFRA) receptors. This may aid in the prediction of clinical evolution and guide the use of specific drug treatments in patients with GIST in Panama.

Rickettsial infection in domestic mammals and their ectoparasites in El Valle de Antón, Coclé, Panamá.

The present research evaluated the presence of Rickettsia spp. on ectoparasites of horses and dogs (using PCR techniques), and their sera (using immunofluorescence assay) in El Valle de Antón town in Panama. A total of 20 horses and 20 dogs were sampled, finding four species of ectoparasites on dogs (the ticks Rhipicephalus sanguineus, Amblyomma ovale, Amblyomma oblongoguttatum, and the flea Ctenocephalides felis), and two tick species on horses (Amblyomma cajennense and Dermacentor nitens). DNA of Rickettsia amblyommii was found in pools of A. cajennense, D. nitens, and R. sanguineus, while Rickettsia felis was detected in C. felis pools. Overall, 70% (14/20) and 65% (13/20) of the horses and dogs, respectively, were seroreactive (titer ≥ 64) to spotted fever group rickettsiae. Sera from six dogs and five horses reacted to R. amblyommii antigens with titers at least four-fold higher than those for the other antigens tested (Rickettsia bellii, Rickettsia parkeri, Rickettsia rhipicephali, R. felis, and R. rickettsii). These serological results, coupled with our molecular findings, suggest that these dogs and horses were infected by Rickettsia amblyommii. More studies need to be realized afford to identify the Rickettsia species responsible for other serological and molecular positive results, and their ecological importance.

Rocky Mountain spotted fever in Panama: a cluster description.

Rocky Mountain spotted fever (RMSF) is a tick-borne infection caused by Rickettsia rickettsii. We report a cluster of fatal cases of RMSF in 2007 in Panama, involving a pregnant woman and two children from the same family.  The woman presented with a fever followed by respiratory distress, maculopapular rash, and an eschar at the site from which a tick had been removed.  She died four days after disease onset.  This is the second published report of an eschar in a patient confirmed by PCR to be infected with R. rickettsii.  One month later, the children presented within days of one another with fever and rash and died three and four days after disease onset. The diagnosis was confirmed by immunohistochemistry, PCR and sequencing of the genes of R. rickettsii in tissues obtained at autopsy. 

Molecular epidemiology of American tegumentary leishmaniasis in Panama.

American tegumentary leishmaniasis is an increasing public health problem in Panama. This study describes the clinical characteristics and the molecular epidemiology of leishmaniasis in Panama over a 5-year period (2004-2008). Additionally, we applied a polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP)-based assay to identify Leishmania species in clinical isolates, skin scrapings, and sandflies specimens. Whereas 60.3% of cases were detected with conventional parasitologic techniques (smear or in vitro culture), the PCR detected 72% positive patients. Our clinical-epidemiologic data corroborate the high incidence of L. (Viannia) panamensis and provide evidence of peridomestic and/or domestic transmission. Mucosal involvement was observed in 4.2% of the patients. The overall natural infection rate with Leishmania in 103 pools of sandflies was 0.46%. Lutzomyia gomezi and Lutzomya panamensis were the prevalent species incriminated as vectors at the capture sites in central Panama. This study contributes to a better knowledge of the current epidemiology of tegumentary leishmaniasis in Panama.

Profile of the first cases hospitalized due to influenza A (H1N1) in Panama City, Panama. May-June 2009.

INTRODUCTION: In April 2009, a novel influenza A (H1N1) virus was identified in patients from Mexico and the United States. From 8 May through 25 June 2009, in the Republic of Panama, 467 cases infected with the same virus were identified, 13 of which were hospitalized at the Santo Tomas Hospital in Panama City. Up to the date of this report, no deaths have been reported in Panama. This study presents the first thirteen cases of Influenza A (H1N1) 2009 that were hospitalized in Panama City. METHODOLOGY: The Santo Tomas Hospital (HST), a third-level institution of the Ministry of Health (MINSA) for adult health care (patients above the age of 14), was designated as the reference center for treating these cases. For this purpose, the norms and criteria established by the system were followed and every patient (case) presenting flu-like symptoms was included (fever equal or greater than 38 masculineC (100.4 masculineF), cough, sore throat, rhinorrhea, lethargy in children under the age of one, and respiratory distress). RESULTS: Seventy-six patients were hospitalized as suspected cases for infection with the influenza A H1N1 2009 virus, of which 13 (17.1%) were confirmed as positive. The clinical picture was characterized by fever (100%), cough (92.3%), rhinorrhea (69.2%), malaise (53.8%), headache (53.8%), and only one case presented gastrointestinal symptoms (diarrhoea). The male:female ratio was 1:2.2. CONCLUSION: The knowledge and technology translation previously acquired through courses to the HST health care providers were the key in controlling the first influenza A (H1N1) 2009 cases.

Hantavirus infection and habitat associations among rodent populations in agroecosystems of Panama: implications for human disease risk.

Hantavirus cardiopulmonary syndrome (HCPS), which is caused by infection with Choclo virus, is uncommon in Panama, yet seropositivity among rural residents is as high as 60%. To clarify the environmental risk factors favoring rodent-to-human transmission, we tested serum from 3,067 rodents captured over a five-year period for antibodies against recombinant N protein of hantavirus by enzyme immunoassay and strip immunoblot. Among 220 seropositive rodents, Oligoryzomys fulvescens, the reservoir of Choclo virus, had the highest overall seroprevalence (23.5%); more abundant rodents (Zygodontomys brevicauda and Sigmodon hirsutus) had lower seroprevalences. In the mixed (combined modern and traditional) productive agroecosystem, the highest seroprevalence was among O. fulvescens captured in residences and in crops grown within 40 meters of a residence, with significantly lower seroprevalence in adjacent pasture and non-productive vegetation. Thus, crop habitats may serve as refugia for invasion into adjacent human residences and suggests several interventions to reduce human infection.