Unraveling the drivers of MERS-CoV transmission.

With more than 1,700 laboratory-confirmed infections, Middle East respiratory syndrome coronavirus (MERS-CoV) remains a significant threat for public health. However, the lack of detailed data on modes of transmission from the animal reservoir and between humans means that the drivers of MERS-CoV epidemics remain poorly characterized. Here, we develop a statistical framework to provide a comprehensive analysis of the transmission patterns underlying the 681 MERS-CoV cases detected in the Kingdom of Saudi Arabia (KSA) between January 2013 and July 2014. We assess how infections from the animal reservoir, the different levels of mixing, and heterogeneities in transmission have contributed to the buildup of MERS-CoV epidemics in KSA. We estimate that 12% [95% credible interval (CI): 9%, 15%] of cases were infected from the reservoir, the rest via human-to-human transmission in clusters (60%; CI: 57%, 63%), within (23%; CI: 20%, 27%), or between (5%; CI: 2%, 8%) regions. The reproduction number at the start of a cluster was 0.45 (CI: 0.33, 0.58) on average, but with large SD (0.53; CI: 0.35, 0.78). It was >1 in 12% (CI: 6%, 18%) of clusters but fell by approximately one-half (47% CI: 34%, 63%) its original value after 10 cases on average. The ongoing exposure of humans to MERS-CoV from the reservoir is of major concern, given the continued risk of substantial outbreaks in health care systems. The approach we present allows the study of infectious disease transmission when data linking cases to each other remain limited and uncertain.

Estimating the Severity and Subclinical Burden of Middle East Respiratory Syndrome Coronavirus Infection in the Kingdom of Saudi Arabia.

Not all persons infected with Middle East respiratory syndrome coronavirus (MERS-CoV) develop severe symptoms, which likely leads to an underestimation of the number of people infected and an overestimation of the severity. To estimate the number of MERS-CoV infections that have occurred in the Kingdom of Saudi Arabia, we applied a statistical model to a line list describing 721 MERS-CoV infections detected between June 7, 2012, and July 25, 2014. We estimated that 1,528 (95% confidence interval (CI): 1,327, 1,883) MERS-CoV infections occurred in this interval, which is 2.1 (95% CI: 1.8, 2.6) times the number reported. The probability of developing symptoms ranged from 11% (95% CI: 4, 25) in persons under 10 years of age to 88% (95% CI: 72, 97) in those 70 years of age or older. An estimated 22% (95% CI: 18, 25) of those infected with MERS-CoV died. MERS-CoV is deadly, but this work shows that its clinical severity differs markedly between groups and that many cases likely go undiagnosed.

The Saudi Thoracic Society guidelines for influenza vaccinations.

Influenza viruses are responsible for the influenza outbreaks that lead to significant burden and cause significant morbidity and mortality worldwide. Based on the core proteins, influenza viruses are classified into three types, A, B, and C, of which only A and B cause significant human disease and so the vaccine is directed against these two subtypes only. The effectiveness of the vaccine depends on boosting the immune system against the serotypes included within it. As influenza viruses undergo periodic changes in their antigen, the vaccine is modified annually to ensure susceptibility. In contrast to other countries, Saudi Arabia faces a unique and challenging situation due to Hajj and Umrah seasons, when millions of people gather at the holy places in Mecca and Madinah, during which influenza outbreaks are commonly found. Such challenges making the adoption of strict vaccination strategy in Saudi Arabia is of great importance. All efforts were made to develop this guideline in an easy-to-read form, making it very handy and easy to use by health care workers. The guideline was designed to provide recommendations for problems frequently encountered in real life, with special consideration for special situations such as Hajj and Umrah seasons and pregnancy.

Epidemiological, demographic, and clinical characteristics of 47 cases of Middle East respiratory syndrome coronavirus disease from Saudi Arabia: a descriptive study.

BACKGROUND: Middle East respiratory syndrome (MERS) is a new human disease caused by a novel coronavirus (CoV). Clinical data on MERS-CoV infections are scarce. We report epidemiological, demographic, clinical, and laboratory characteristics of 47 cases of MERS-CoV infections, identify knowledge gaps, and define research priorities. METHODS: We abstracted and analysed epidemiological, demographic, clinical, and laboratory data from confirmed cases of sporadic, household, community, and health-care-associated MERS-CoV infections reported from Saudi Arabia between Sept 1, 2012, and June 15, 2013. Cases were confirmed as having MERS-CoV by real-time RT-PCR. FINDINGS: 47 individuals (46 adults, one child) with laboratory-confirmed MERS-CoV disease were identified; 36 (77%) were male (male:female ratio 3·3:1). 28 patients died, a 60% case-fatality rate. The case-fatality rate rose with increasing age. Only two of the 47 cases were previously healthy; most patients (45 [96%]) had underlying comorbid medical disorders, including diabetes (32 [68%]), hypertension (16 [34%]), chronic cardiac disease (13 [28%]), and chronic renal disease (23 [49%]). Common symptoms at presentation were fever (46 [98%]), fever with chills or rigors (41 [87%]), cough (39 [83%]), shortness of breath (34 [72%]), and myalgia (15 [32%]). Gastrointestinal symptoms were also frequent, including diarrhoea (12 [26%]), vomiting (ten [21%]), and abdominal pain (eight [17%]). All patients had abnormal findings on chest radiography, ranging from subtle to extensive unilateral and bilateral abnormalities. Laboratory analyses showed raised concentrations of lactate dehydrogenase (23 [49%]) and aspartate aminotransferase (seven [15%]) and thrombocytopenia (17 [36%]) and lymphopenia (16 [34%]). INTERPRETATION: Disease caused by MERS-CoV presents with a wide range of clinical manifestations and is associated with substantial mortality in admitted patients who have medical comorbidities. Major gaps in our knowledge of the epidemiology, community prevalence, and clinical spectrum of infection and disease need urgent definition. FUNDING: None.

Effects of a simple protocol on infective complications in intensive care unit patients undergoing percutaneous dilatational tracheostomy.

In our intensive care unit we monitored infection in 228 patients who underwent percutaneous dilatational tracheostomy (PDT). In the first phase of the study 128 PDTs were performed during a 33-month period and there were 41 infection complications (nosocomial pneumonia, bacteremia with sepsis, and septic shock) in the perioperative period (immediately prior to and for 5 days after PDT). A significant risk factor among patients with nosocomial pneumonia was empirical administration of inappropriate antibiotics, compared to appropriate antibiotics (34% versus 4%, p < 0.001). In the second phase of the study (a 30-month period), a simple antibiotics protocol was prospectively applied to 100 PDT patients. The protocol virtually eliminated inappropriate antibiotic drug use immediately prior to PDT and contributed to a significant reduction in perioperative infective complications (pre-protocol 32% versus protocol 11%, p < 0.001).

Mycobacterium tuberculosis susceptibility in Saudi Arabia.

OBJECTIVE: To present the available susceptibility data of Mycobacterium tuberculosis (M. tuberculosis) isolates from the Kingdom of Saudi Arabia (KSA) published in peer-reviewed journals. METHODS: In a meta-analysis, studies published between 1966 and 2001 were included. Publication sites include Medline-indexed and non-indexed. Numbers of grown and resistant isolates were tabulated for first-line anti-tuberculosis agents. RESULTS: Twelve studies met the pre-set criteria. Data on 6,316 isolates between 1979 and 2000 were available. Resistance to at least one agent of the first-line anti-tuberculosis agents was 18.4%. Monoresistance to a single first-line agent was found in 10.9%, while polyresistance was noted in 7.6%. Multidrug-resistant M. tuberculosis was noted in 5.7% of all isolates. Resistance to isoniazid was most common noted in 11% of isolates. Resistance rates to other agents were: rifampin 9.7%, streptomycin 9.1%, pyrazinamide 3.1%, and ethambutol 2.5%. The overall resistance rate to at least one agent was not statistically different in isolates grown between 1979-1991 (18.5%) and 1989-2000 (18.3%). There were large regional variations and higher resistance rates in the Western and Southern regions. CONCLUSION: Mycobacterium tuberculosis resistance rates to first-line antituberculosis agents and multidrug-resistant M. tuberculosis are high in KSA. A survey and monitoring program for drug-resistant tuberculosis will determine resistance rates at the community level.

Extrapulmonary tuberculosis, epidemiology and patterns in Saudi Arabia.

Annual incidence rates of extrapulmonary tuberculosis have been increasing over the last few years in the Kingdom of Saudi Arabia. True rates may even be higher due to incomplete reporting. Diagnosis of this condition requires high clinical suspicion, special diagnostic procedures, special staining, and culture media for acid fast bacilli. Delayed diagnosis results in increasing morbidity, mortality, and cost to the health care system. Particularly in areas of high endemicity of Mycobacterium tuberculosis, clinicians should be aware of the various forms of extrapulmonary tuberculosis. The available epidemiology and patterns of various forms of extrapulmonary tuberculosis in the Kingdom of Saudi Arabia are presented in this review.

Extrapulmonary tuberculosis, epidemiology and patterns in Saudi Arabia.

Annual incidence rates of extrapulmonary tuberculosis have been increasing over the last few years in the Kingdom of Saudi Arabia. True rates may even be higher due to incomplete reporting. Diagnosis of this condition requires high clinical suspicion, special diagnostic procedures, special staining, and culture media for acid fast bacilli. Delayed diagnosis results in increasing morbidity, mortality, and cost to the health care system. Particularly in areas of high endemicity of Mycobacterium tuberculosis, clinicians should be aware of the various forms of extrapulmonary tuberculosis. The available epidemiology and patterns of various forms of extrapulmonary tuberculosis in the Kingdom of Saudi Arabia are presented in this review.