High Prevalence Of Infectious Diseases Research Articles

Convergence of a diabetes mellitus, protein energy malnutrition, and TB epidemic: the neglected elderly population.

BackgroundOn a global scale, nearly two billion persons are infected with Mycobacterium tuberculosis. From this vast reservoir of latent tuberculosis (TB) infection, a substantial number will develop active TB during their lifetime, with some being able to transmit TB or Multi-drug- resistant (MDR) TB to others. There is clinical evidence pointing to a higher prevalence of infectious diseases including TB among individuals with Diabetes Mellitus (DM). Furthermore, ageing and diabetes mellitus may further aggravate protein-energy malnutrition (PEM), which in turn impairs T-lymphocyte mediated immunologic defenses, thereby increasing the risk of developing active TB and compromising TB treatment. This article aims to a) highlight synergistic mechanisms associated with immunosenescence, DM and PEM in relation to the development of active TB and b) identify nutritional, clinical and epidemiological research gaps.MethodsTo explore the synergistic relationship between ageing, DM, tuberculosis and PEM, a comprehensive review was undertaken. The MEDLINE and the Google Scholar databases were searched for articles published from 1990 to March 2015, using different MESH keywords in various combinations.ResultsAgeing and DM act synergistically to reduce levels of interferon gamma (IFN- γ), thereby increasing susceptibility to TB, for which cell mediated immunity (CMI) plays an instrumental role. These processes can set in motion a vicious nutritional cycle which can predispose to PEM, further impairing the CMI and consequently limiting host defenses. This ultimately transforms the latent TB infection into active disease. A clinical diagnostic algorithm and clinical guidelines need to be established for this population.ConclusionGiven the increase in ageing population with DM and PEM, especially in resource-poor settings, these synergistic tripartite interactions must be examined if a burgeoning TB epidemic is to be averted. Implementation of a comprehensive, all-encompassing approach to curb transmission is clearly indicated. To this end, clinical, nutritional and epidemiological research gaps must be addressed without a delay.

Diagnosis dan Penatalaksanaan Uveitis dalam Upaya Mencegah Kebutaan

Uveitis is an inflammation of the uvea which may result in blindness. Uveitis may be caused by limited inflamation of the uveal tract, manifestation of systemic diseases (autoimmune, infection, cancer), expansion of inflammation in the cornea and sclera, trauma or idiopathic. Anterior uveitis is an inflammation of the iris and cilliary body with symptoms of pain, red eye, photophobia, and decrease in visual acuity. Intermediate uveitis is the inflammation of the pars plana and frequently involves anterior vitreous and posterior uveitis. Clinical manifestation of intermediate uveitis is usually mild without red eye and pain, however vision may decrease due to macular edema and cell aggregation in vitreous. Posterior uveitis is an inflammation involving choroid layer, which is common in developing countries due to high prevalence of infectious diseases (toxoplasmosis, tuberculosis, HIV, syphilis). Patient may complain of blurry vision but not accompanied by pain, red eye, and photophobia. Complications of posterior uveitis are cataract, glaucoma, macular edema, keratopathy, turbidity of vitreous, retinal detachment, and optic nerve atrophy. The prognosis of posterior uveitis is worse than anterior uveitis. Panuveitis is an inflammation of the uvea and surrounding structures (retina, vitreous). Diagnosis is made based on anamnesis, ophthalmic examination, laboratory examination, and imaging. Treatment of uveitis is intended to reduce inflammation, minimize structural destruction, prevent blindness, reduce pain and photophobia. Corticosteroid and immunosuppresant are the drugs of choice to manage the inflammation, where NSAID is used to reduce pain and cyclopegic administration to prevent posterior synechiae. Antimicrobial is given if uveitis is caused by infection. Underlying diseases of uveitis must be treated comprehensively to prevent further progression, complications and blindness. Normal 0 false false false IN X-NONE X-NONE

High Prevalence of Infectious Diseases and Drug-Resistant Microorganisms in Asylum Seekers Admitted to Hospital; No Carbapenemase Producing Enterobacteriaceae until September 2015

IntroductionThe current refugee crisis emphasizes the need for information on infectious diseases and resistant microorganisms in asylum seekers with possible consequences for public health and infection control.MethodsWe collected data from asylum seekers admitted to our university hospital or who presented at the Emergency Department (n = 273). We collected general and demographic characteristics including country of origin, the reason of presentation, and the screening results of multi-drug resistant organisms.Results67% of the patients were male with a median age of the study group of 24 years (IQR 15–33); 48% of the patients had an infectious disease—predominantly malaria with P. vivax or tuberculosis. Patients also reported with diseases which are less common—e.g. leishmaniasis, or even conditions rarely diagnosed in Europe—e.g. louse borne relapsing fever. A carriage rate of 31% for multi-drug resistant microorganisms (MDRO) was observed, with ESBL-expressing E.coli (n = 20) being the most common MDRO. No carriage of Carbapenemase Producing Enterobacteriaceae was found.ConclusionThe current refugee crisis in Europe challenges hospitals to quickly identify and respond to communicable diseases and the carriage of MDRO. A rapid response is necessary to optimize the treatment of infectious diseases amongst asylum seekers to maximize infection control.

Profiling of Oral and Nasal Microbiome in Children With Cleft Palate.

To identify the oral and nasal microbial profile of cleft palate children and control children and to reveal interrelationships between the microbiome and the high prevalence of infectious diseases. Saliva and nasal samples of 10 cleft palate children and 10 age-matched control children were analyzed. Total microbial genomic DNA was isolated, polymerase chain reaction-denaturing gradient gel electrophoresis was applied to obtain fingerprints, and selected bands on fingerprints were sequenced. The results revealed a significantly lower saliva microbial diversity in cleft children and a different microbial component in both saliva and nares in children with cleft palate. A higher component similarity between the oral and nasal samples was found in the cleft group than in the control group. Lautropia species and Bacillus species were significantly less present among the saliva samples of cleft group. Dolosigranulum species and Bacillus species were significantly fewer in the nasal cavity of cleft group. Streptococcus species became much more predominant in the nasal cavity of the cleft group than in that of the control group. A disturbed ecological ecosystem is found in oral and nasal microbiome of children with cleft palate as a consequence of the abnormal communication between the two cavities. Further studies are needed to explore the relationship between the disturbed microbiome and diseases.

Infectious Diseases in Sub-Saharan Immigrants to Spain.

Immigrants may be carriers of infectious diseases because of the prevalence of these diseases in their country of origin, exposure during migration, or conditions during resettlement, with this prevalence being particularly high in sub-Saharan Africans. We performed a retrospective review of 180 sub-Saharan immigrants screened for infectious diseases at an International Health Center from January 2009 to December 2012. At least one pathogenic infectious disease was diagnosed in 72.8% patients: 60.6% latent tuberculosis infection, 36.8% intestinal parasites (intestinal protozoa or helminths), 28.1% helminths, 14.8% hepatitis B surface antigen positive, 1.2% anti-hepatitis C virus positive, 1.2% human immunodeficiency virus-positive, and 1.2% malaria. Coinfections were present in 28.4%. There was significant association between eosinophilia (absolute count or percentage) or hyper-IgE and the presence of helminths (P< 0.001). Relative eosinophilia and hyper-IgE were better indicators of helminth infection than absolute eosinophilia, particularly for schistosomiasis and strongyloidiasis. We found a high prevalence of infectious diseases in sub-Saharan immigrants, which could lead to severe health problems (in the absence of prompt treatment), representing a high cost to the public health system and possible transmission in the host country. Accurate screening and tailored protocols for infectious diseases are recommended in sub-Saharan immigrants.

Fortalecimiento de la estrategia de atención primaria en salud en territorios del municipio de Cali, 2014

La ciudad de Cali, Colombia, se caracteriza por un desarrollo urbanístico asimétrico donde alternan zonas de pobreza y riqueza extremas, con sus variaciones en el perfil de morbimortalidad. La Secretaria de Salud Municipal ha desarrollado un proyecto de fortalecimiento de la atención primaria en salud en 11 territorios seleccionados por sus condiciones de riesgo y ha desplegado un trabajo de campo para caracterizar las familias en sus riesgos individuales, familiares y comunitarios. Materiales y métodos: La información se recolectó a partir de la sistematización de una ficha familiar que contiene información sobre características de la vivienda, datos demográficos de las familias, la presencia de riesgos en salud y la asistencia a programas de promoción y protección específica. Se establecieron las prevalencias para los factores de riesgo y sus intervalos de confianza. Resultados: Se recolectó información de 7.419 familias en el año 2013 y 2.065 en el 2014 que agrupan a cerca de 36.000 personas. Las prevalencias más significativas se encontraron para la inasistencia a los programas de crecimiento y desarrollo (26%), mujeres sin asistencia al programa de planificación familiar (52%), sobrepeso (38%) y personas con glucometrías alteradas (33%). En relación con los riesgos del hábitat se encontró un promedio de 13% de viviendas en malas condiciones estructurales y de higiene y un hacinamiento del 8,3%. A través de estos indicadores se establece un perfil de riesgos en las familias para la intervención por parte de la red de servicios.

Prevalence and Knowledge Assessment of HIV and Non-Communicable Disease Risk Factors among Formal Sector Employees in Namibia.

IntroductionThe burden of non-communicable diseases (NCDs) is growing in sub-Saharan Africa combined with an already high prevalence of infectious disease, like HIV. Engaging the formal employment sector may present a viable strategy for addressing both HIV and NCDs in people of working age. This study assesses the presence of three of the most significant threats to health in Namibia among employees in the formal sector: elevated blood pressure, elevated blood glucose, and HIV and assesses the knowledge and self-perceived risk of employees for these conditions.MethodsA health and wellness screening survey of employees working in 13 industries in the formal sector of Namibia was conducted including 11,192 participants in the Bophelo! Project in Namibia, from January 2009 to October 2010. The survey combined a medical screening for HIV, blood glucose and blood pressure with an employee-completed survey on knowledge and risk behaviors for those conditions. We estimated the prevalence of the three conditions and compared to self-reported employee knowledge and risk behaviors and possible determinants.Results25.8% of participants had elevated blood pressure, 8.3% of participants had an elevated random blood glucose measurement, and 8.9% of participants tested positive for HIV. Most participants were not smokers (80%), reported not drinking alcohol regularly (81.2%), and had regular condom use (66%). Most participants could not correctly identify risk factors for hypertension (57.2%), diabetes (57.3%), or high-risk behaviors for HIV infection (59.5%). In multivariate analysis, having insurance (OR:1.15, 95%CI: 1.03 – 1.28) and a managerial position (OR: 1.29, 95%CI: 1.13 – 1.47) were associated with better odds of knowledge of diabetes.ConclusionThe prevalence of elevated blood pressure, elevated blood glucose, and HIV among employees of the Namibian formal sector is high, while risk awareness is low. Attention must be paid to improving the knowledge of health-related risk factors as well as providing care to those with chronic conditions in the formal sector through programs such as workplace wellness.

Quality of life and its correlates in diabetic outpatients in Swaziland.

Diabetes is a chronic disease requiring frequent monitoring that may be accompanied by considerable quality of life (QOL) burden. Low- and middle-income countries such as Swaziland are facing a double disease burden exacerbated by the high prevalence of infectious diseases. This study aimed to understand the QOL and its correlates in diabetic outpatients in Swaziland. Participants were consecutively recruited during their routine visits to a referral hospital in Swaziland. Face-to-face interviews were conducted with outpatients using the Diabetes-39 questionnaire to measure their QOL. Raw scores were transformed to a standard domain-specific score using linear transformation with scores ranging from 0 (lowest impact) to 100 (highest impact). Among the 340 participants in this cross-sectional study anxiety and worry was the most affected QOL domain. In multiple linear regression analyses, the presence of complications and/or comorbidities, low income, limited education and being on insulin therapy, showed higher impacts of diabetes on the participants' QOL. The high impact of diabetes on anxiety and worry QOL score highlights the need to address diabetic patients' psychological wellbeing in the clinical management of diabetes. An integrated diabetes care program that takes into account the impacts of sociodemographic and clinical factors on QOL may improve the QOL of diabetic patients.

Rheumatology in India--quo vadis?

Rheumatology has been a neglected subspecialty in India. A staggering patient load, a severely inadequate number of trained rheumatology specialists, therapeutic nihilism and limited advocacy are some of the critical challenges that confront rheumatology care, and possibly explain the high rates of reliance on complementary and alternative medicines in India. Disease spectrum and treatment patterns are not remarkably different from those in other countries, but biologic agents have limited use and are administered for short periods only. Consequently, outcomes in India do not yet match those reported in developed countries. Furthermore, the high prevalence of infectious diseases continues to be a major contributor to mortality in patients with rheumatic disorders such as systemic lupus erythematosus. Several tropical diseases with rheumatic manifestations are relevant in India, including chikungunya, brucellosis, leptospirosis, dengue and melioidosis. To address the many problems with rheumatology care in India, curricular reforms, capacity building, patient education and political support are sorely needed.

The Impact of Discrimination on the Spread of Infectious Diseases in Complex Networks

This paper proposes a novel model combining an epidemic dynamics and an opinion dynamics to investigate the impact of epidemic-related opinion dynamics on the spreading of infectious diseases in complex networks. We assume that, the outcomes of opinion dynamics on the behavior of asymptomatically infected individuals who have known their infected state, could not only reduce their transmission probabilities, but also could increase their transmission probabilities. This assumption has rarely been considered for modeling the interactions among epidemic dynamics, opinion dynamics and the exchange of human behaviors. We find that when the epidemic-related opinion dynamics exist, a higher randomness of individuals will simultaneously lead to a higher prevalence of infectious diseases and a lower social discrimination perceived by infected individuals. Furthermore, if the positive external global impact exceeds a certain critical value, there is an abrupt disappearance of infection owing to the contribution of opinion dynamics. Based on our results, some suggestions are given to reduce the spreading of epidemic diseases.

Comorbilidad de tuberculosis y diabetes: problema aún sin resolver

Co-morbidity between tuberculosis and diabetes has been described since the early 20th century. In developed countries, where there has been a decrease of infectious diseases with an increase of non-communicable diseases, as well as those countries who still have a high prevalence of infectious diseases but an increase of non-communicable diseases, it is observed that the prevalence of co-morbidity between tuberculosis and diabetes is increasing, making clinical management and control at the public health level a new challenge for health systems. This review aims to show the current available evidence that can inform research lines being developed to understand the problem. In countries like Peru, where there is an epidemiological transition, further research could allow us to understand and describe in a better way the characteristics and impact of this co-morbidity.

Proposal to utilize simplified Swensen protocol in diagnosis of isolated pulmonary nodule

The problem of diagnosing whether a solitary pulmonary nodule is benign or malignant is even greater in developing countries due to a higher prevalence of infectious diseases. These infections generate a large number of patients who are generally asymptomatic and with a pulmonary nodule that cannot be accurately defined as having benign or malignant etiology. To verify the percentages of benign versus malignant non-calcified nodules, the length of time after contrast agent injection is spiral computed tomography (CT) most sensitive and specific, and whether three postcontrast phases are necessary. We studied 23 patients with solitary pulmonary nodules identified on chest radiographs or CT. Spiral scans were obtained with Swensen protocol, but at 3, 4, and 5 min after contrast injection onset. Nodules were classified as benign or malignant by histopathological examination or by an absence or presence of growth after 2 years of follow-up CT. Of the 23 patients studied, 18 (78.2%) showed a final diagnosis of benign and five (21.7%) malignant nodules. Despite the small sample size, we obtained results similar to those of Swensen et al., with 80.0% sensitivity, 55.5% specificity, and 60.8% accuracy. Four minutes gave the greatest mean enhancement in both malignant and benign lesions. Small non-calcified benign nodules were much more frequent than malignant nodules. The best time for dynamic contrast-enhanced CT density analysis was 4 min postcontrast. As well as saving time and money, this simplified Swensen protocol with only precontrast and 4 min postcontrast phases also reduces patient exposure to ionizing radiation.

Distribution patterns of variability for 18 immune system genes in Amerindians – relationship with history and epidemiology

Native American populations generally have a higher prevalence of infectious diseases than non-Native populations and this fact can induce different pressures in their immune system. We investigated the patterns of population differentiation (FST ) of 32 polymorphisms related to adaptive immune response in four Native American populations (Aché, Guarani-Kaiowá, Guarani-Ñandeva and Kaingang), and the results were compared with the three major world population data [Yoruba of Ibadan, Nigeria (YRI), Utah residents with northern and Western Europe ancestry (CEU) and Han Chinese of Beijing, China (CHB)] available in the HapMap database. The Aché clearly differentiated from the other Amerindians, but when all Native Americans were compared with the samples of other ethnic groups the lowest difference (0.08) was found with CHB (Asians), the second lowest (0.15) with YRI (Africans) and the most marked with CEU (European-derived). The considerable intra and interethnic differences found can be explained both in terms of diverse evolutionary distances and more recent environmental pathogen exposures; and they should be appropriately considered prior to any specific public health action.

Disgust and Contamination: A Cross-National Comparison of Ghana and the United States

The emotion of disgust, with feelings of revulsion and behavioral withdrawal, make it a prime emotion to aid in the avoidance of sources of contamination, including sources of potential infectious disease. We tested the theory that living in a region with a historically high prevalence of infectious diseases would promote higher levels of disgust and contamination sensitivity as a protective measure. A sample of undergraduates from Ghana (n = 103, 57 women), a country with a historically high prevalence of infectious diseases, showed significantly higher scores on scales assessing disgust, contamination, and disease susceptibility than a sample of undergraduates from the United States (n = 96, 58 women), a country with lower levels of disease threat. Contamination sensitivity mediated the national differences in disgust. Disgust connoting contamination also produced larger cross-national effect sizes than other types of disgust. Finally, a factor analysis on the Ghanaian responses to one of the disgust scales did not resemble the usual three-factor solution found in West. Taken together, the results were consistent with the hypothesis that a region with a higher prevalence of infectious disease threats would produce greater sensitivity to disgust and contamination than seen in lower disease threat regions. This first study on disgust in Africa showed that disgust sensitivity could differ considerably from that in the West.

The regional profile of antibiotic prescriptions in Italian outpatient children

To evaluate paediatric antibiotic prescription patterns in Italy in an extra-hospital setting at the national, regional, and Local Health Unit (LHU) level. Data sources were regional prescription databases. Eight Italian regions participated in the study providing data for the year 2008, with two exceptions (where the data for 2009 and 2006 were provided instead). A total of 4,828,569 children were included: 58% of the Italian population under 15years old. Antibiotic prevalence rates, prescription rates and prescriptions distribution by class were evaluated at the regional and LHU levels. The correlation among mean latitude, Human Development Index (HDI), hospitalisation rate, satisfaction index for the National Health Service, number of paediatricians per 1,000 resident children and prevalence rate was evaluated by regions. The estimated pooled average prevalence rate was 50.5% (95%CI 45.7-55.3). Between-regions prevalence rates ranged from 42.6% to 62.1% and at the LHU level they ranged from 35.6% to 68.5%. There was a trend indicating that in southern regions antibiotics are more frequently prescribed than in the northern and central regions (Cochrane-Armitage test Z = -187.5 p < 0.0001). Overall, penicillin covered 53.1% of antibiotic prescriptions, with differences between regions ranging from 39.2% to 62.5%. A direct correlation was found between the prevalence rate and HDI (p = 0.031), while an inverse correlation was found with paediatricians per 1,000 resident children (p = 0.038). We found that relevant differences exist between the northern and the southern part of the country, and the heterogeneity among LHUs is higher. The greater use of antibiotics in the southern regions is related to lower HDI and does not seems to be justified by the higher prevalence of infectious diseases.

The health of newly arrived refugees to the Top End of Australia: results of a clinical audit at the Darwin Refugee Health Service

Accurate data on the health of refugees in primary care is vital to inform clinical practice, monitor disease prevalence, influence policy and promote coordination. We undertook a retrospective clinical audit of newly arrived refugees attending the Darwin refugee primary health service in its first 12 months of operation. Data were collected from the clinic files of refugee patients who attended for their initial health assessment from 1 July 2009 to 30 June 2010 and were analysed descriptively. Among 187 refugees who attended in 2009-2010, ~60% were from Asia and 42% were female. The most common diagnoses confirmed by testing were vitamin D deficiency (23%), hepatitis B carrier status (22%), tuberculosis infection (18%), schistosomiasis (17%) and anaemia (17%). The most common documented health conditions recorded by the GPs were vitamin D deficiency or insufficiency (66%), followed by schistosomiasis (24%) and dental disease (23%). This clinical audit adds to a limited evidence base suggesting a high prevalence of infectious disease, nutrient deficiency and dental disease among refugees arriving to Australia. GPs involved in the care of refugees must be aware of the epidemiology of disease in this group, as some diseases are rare among the general Australian population. Our results also highlight the ongoing need for advocacy to address service constraints such as limited public dental access for this population.

Different patterns of dermatological presentations in patients co-infected with human immunodeficiency virus and hepatitis C virus (HCV), and those infected with HCV alone

Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) share the same transmission routes. About 30% of HIV-positive patients are co-infected with HCV. Of the various HCV-related extrahepatic events, those involving the skin may be the first sign of infection. To specify the skin presentations in patients co-infected with HIV and HCV (co-infected patients; CP) and compare them with those found in patients with HCV mono-infection (mono-infected patients; MP). This was a cross-sectional study, in which the studied population consisted of MP and CP from a tertiary hospital in the South of Brazil, who underwent complete skin examination and laboratory tests. In total, 201 patients were assessed, of whom 108 were CP, and 93 were MP. Pruritus tended to be more common in MP. MP also had significantly more dermatological conditions (mean of 5.2) than CP (mean of 4.5). In total, 104 different skin diseases were identified. There was a higher prevalence of infectious diseases and pigmentation disorders, such as verruca vulgaris and facial melasma, in CP, whereas trunk and facial telangiectasias, palmar erythema, and varicose veins were more common in MP. We found a high prevalence of skin conditions both in MP and in CP; however, the patterns of the dermatological conditions were different. CP were found to have significantly fewer skin lesions than MP, but had a higher prevalence of infectious and pigmentation disorders. By contrast, vascular conditions were more common in MP.

Herd Immunity/Herd Infection: Cultural Artifacts of Marginalization and the Dynamics of AIDS

AbstractWe examine conditions under which high prevalence of infectious disease can become endemic within a community, in effect constituting a state of 'herd infection' inverse to epidemiological herd immunity. For something like AIDS, under such circumstances, a single behavioral lapse or adverse accident will probably be a death sentence.

Giardia lamblia Infection and Its Implications for Vitamin A Liver Stores in School Children

Background: Vitamin A deficiency (VAD) is a nutritional problem affecting the health of people in developing countries because VAD compromises innate and adaptive immunity, increasing a person’s predisposition toward infectious diseases. In addition, a high prevalence of infectious diseases continues to be a problem in developing countries, including Giardia lamblia. G. lamblia may be related to VAD because of its ability to change the intestinal architecture, thereby compromising the absorption of vitamin A. The aim of this study was to evaluate the effect of giardiasis on serum retinol levels and vitamin A liver stores in school children. Methods: Thirty Giardia-infected school children participated in this study. Vitamin A liver stores were evaluated with the modified relative dose response (MRDR) technique, and antiparasitic treatment was administered. In addition, anthropometric and dietary data were collected. Results: According to anthropometric indicators (age-appropriate Z scores for weight, height and body mass index) and daily vitamin A intake, the children had a normal nutritional status. Although the mean serum retinol levels did not change significantly after treatment for Giardia (p > 0.05), the MRDR values showed significant improvement (p < 0.002). Conclusion: Giardiasis not only compromises the vitamin A status through intestinal malabsorption, it also causes profound mobilization of liver retinol stores.

Effect of Giardiasis on Vitamin A Status in Mexican School Children

ObjectiveVitamin A deficiency (VAD) is a nutritional problem affecting the health of people in developing countries because VAD compromises innate and adaptive immunity, increasing a person's predisposition toward infectious diseases. In addition, a high prevalence of infectious diseases continues to be a problem in developing countries, including Giardia lamblia. Giardiasis may be related to VAD because of its ability to change the intestinal architecture, thereby compromising the absorption of vitamin A. The aim of this study was to evaluate the effect of giardiasis on vitamin A status in school children.MethodsThirty Giardia‐infected school children participated in this study. Vitamin A status was evaluated at baseline during active giardiasis and six months after anti‐parasitic treatment was administered. In addition, anthropometric and dietary data were collected.ResultsAccording to anthropometric indicators (age‐appropriate Z scores for weight, height, and body mass index) the children had a normal nutritional status. Although mean dietary vitamin A adequacy was &gt;100%, only 73% (n=22) of subjects had an adequate daily vitamin A intake. There was a significant improvement on serum retinol levels once giardiasis was treated, leading to a 64.6% reduction of subclinical VAD (P&lt;0.02).ConclusionGiardia lamblia has a negative effect on vitamin A status of Mexican school children, increasing their predisposition toward infectious diseases.