The first sixty days of COVID-19 in a humanitarian response setting: a descriptive epidemiological analysis of the outbreak in South Sudan

Introduction

the coronavirus disease 2019 (COVID-19) was declared a pandemic on March 11, 2020. South Sudan, a low-income and humanitarian response setting, reported its first case of COVID-19 on April 5, 2020. We describe the socio-demographic and epidemiologic characteristics of COVID-19 cases in this setting.

Methods

we conducted a cross-sectional descriptive analysis of data for 1,330 confirmed COVID-19 cases from the first 60 days of the outbreak.

Results

among the 1,330 confirmed cases, the mean age was 37.1 years, 77% were male, 17% were symptomatic with 95% categorized as mild, and the case fatality rate was 1.1%. Only 24.7% of cases were detected through alerts and sentinel site surveillance, with 95% of the cases reported from the capital, Juba. Epidemic doubling time averaged 9.8 days (95% confidence interval [CI] 7.7 - 13.4), with an attack rate of 11.5 per 100,000 population. Test positivity rate was 18.2%, with test rate per 100,000 population of 53 and mean test turn-around time of 9 days. The case to contact ratio was 1: 2.2.

Conclusion

this 2-month initial period of COVID-19 in South Sudan demonstrated mostly young adults and men affected, with most cases reported as asymptomatic. Systems´ limitations highlighted included a small proportion of cases detected through surveillance, low testing rates, low contact elicitation, and long collection to test turn-around times limiting the country´s ability to effectively respond to the outbreak. A multi-pronged response including greater access to testing, scale-up of surveillance, contact tracing and community engagement, among other interventions are needed to improve the COVID-19 response in this setting.

The Coulter Counter Model S Plus--the shape of things to come

The Coulter Counter Model S Plus is a 12 parameter haematological analyser designed for service use in haematology laboratories. Eight parameters are standard in current routine haematological practice; the seven parameters generated by the Model S and a platelet count. The method of platelet counting is unique. The remaining parameters are new and comprise the platelet-crit, the mean platelet volume and size distribution measurements for both platelets and red cells. A description of the instrument is given including differences from the Model S. The new parameters are discussed in detail. Instrument precision is assessed in terms of linearity, reproducibility, drift, carry-over and protein build-up. The results of all are impressive. Instrument accuracy is assessed in detail; white cell count, red cell count, haemoglobin concentration and mean corpuscular volume being compared with those values measured by the Model S; the Model S Plus haematocrit is compared with the microhaematocrit and platelet counts with those from the Thrombocounter C/Thrombofuge system. All correlations are very satisfactory. Normal values are defined for the new parameters. Instrument design and function are assessed and reagent consumption quoted. Cell control reagents have been evaluated. A realistic hourly throughput for the Model S Plus is 70-80 samples.

Comparison of silver sulphadiazine 1 per cent, silver sulphadiazine 1 per cent plus chlorhexidine digluconate 0.2 per cent and mafenide acetate 8.5 per cent for topical antibacterial effect in infected full skin thickness rat burn wounds

Silver sulphadiazine 1 per cent (SS), silver sulphadiazine 1 per cent plus chlorhexidine digluconate 0.2 per cent (SS + CD 0.2 per cent) and mafenide acetate 8.5 per cent (MA) were compared to assess the antibacterial effect of once daily application on experimental rat 20 per cent full skin thickness burn wounds seeded 24 h earlier with 10(8) microorganisms originally isolated from infected wounds of burned patients. Separate series evaluated Staph. aureus, Enterococcus faecalis, Enterobacter cloacae and Ps. aeruginosa. The mean concentration of all four organisms recovered after 1 week from full thickness biopsies of eschar and from separate biopsies of subjacent muscle was less in MA and SS + CD 0.2 per cent treated animals compared with those treated with SS alone. The mean concentration in muscle and eschar following treatment with MA was less for wounds seeded with Staph. aureus and Ps. aeruginosa than with SS + CD 0.2 per cent treatment, while the mean concentration in eschar application of SS + CD 0.2 per cent was less than with MA for E. faecalis seeded wounds.

Fetal biophysical profile and perinatal death

Antepartum assessment of 5034 high-risk pregnancies to predict perinatal death included five biophysical variables (nonstress test, fetal breathing movements, fetal movements, fetal tone, and amniotic fluid volume) which combined to form a biophysical profile score. We assessed 4148 fetuses within seven days of delivery. The ability of each variable to predict perinatal death was expressed as the likelihood ratio, which incorporates sensitivity and specificity into one number. The predictive ability was most accurate with fetal movement (likelihood ratio 48.1) and the combined biophysical profile score (likelihood ratio 51.0). The biophysical profile score was more likely to predict perinatal death due to asphyxia (seven of eight) than lethal anomaly (six of 19). The overall perinatal mortality was 7.6 per 1000 total births. The perinatal mortality rate was 1.0 for a normal biophysical profile score, 31.3 for an equivocal score, and 200.0 for an abnormal score. The false-negative rate for the biophysical profile score was 0.7 per 1000.

Amniotic fluid phosphatidylglycerol and phosphatidylcholine phosphorus as predictors of fetal lung maturity

The contents of phosphatidylglycerol and phosphatidylcholine phosphorus in amniotic fluid (10,000 X g pellets) were studied as predictors of fetal lung maturity. The presence of phosphatidylglycerol predicted the absence of neonatal respiratory distress syndrome with 99% probability. When phosphatidylglycerol was absent, phosphatidylcholine phosphorus was a reliable predictor if measured 3 to 7 days before delivery. The probability that respiratory distress syndrome would not occur was 94% when phosphatidylcholine phosphorus was greater than 6. When measurement was performed within 2 days of delivery, the probability that respiratory distress syndrome would not occur fell to 69%. As measured in amniotic fluid, phosphatidylglycerol and phosphatidylcholine phosphorus are reliable antenatal predictors of fetal pulmonary maturity and, therefore, are useful in the management of a number of obstetric conditions.

The effect of vaginal administration of various doses of prostaglandin E2 gel on cervical ripening and induction of labor

Eighty patients with a Bishop score of less than or equal to 4 were randomly administered vaginal triacetin gel containing placebo or prostaglandin E2 in 1, 2, and 3 mg doses. Twelve to sixteen hours later, those not in labor underwent oxytocin induction. Increasing doses of prostaglandin were effective in ripening the cervix, and the higher doses were associated with significant success in inducing labor.

Antepartum fetal assessment using a fetal biophysical profile score

The application of the fetal biophysical profile score in the management of 2,400 high-risk pregnancies was assessed. The negative predictive value for normal perinatal outcome was not improved compared to single variable tests. The positive predictive value for abnormal perinatal outcome was improved. The overall perinatal mortality in 2,485 fetuses was 9.2 per 1,000. In the 1,980 fetuses with a normal biophysical profile score within 7 days of delivery, excluding lethal anomalies, the perinatal mortality was 1 per 1,000. Fetal movement counting is supported as the most valid and appropriate test for universal fetal screening.

Comparison of natural and synthetic prostaglandin E2 tablets in labour induction

A multicentre, randomized, double-blind trial compared the efficacy and safety of and tolerance to natural and synthetically produced prostaglandin E2 tablets in the induction of labour in 202 women. The compounds were similarly effective, inducing labour in approximately 66% of patients. The total dose required and the interval between induction and delivery were similar in the two groups, as were the Apgar scores at 1 and 5 minutes and the incidence of maternal and fetal side effects.

Assessment of fetal lung maturity: relationship of gestational age and pregnancy complications to phosphatidylglycerol levels

Phosphatidylglycerol (PG) was measured in the pellet fraction of 863 amniotic fluid samples, and charts were reviewed for maternal disease, duration of gestation at collection, and outcome of pregnancy. PG was present at 32 to 34 weeks' gestation in 24.1% of samples; at 35 to 36 weeks, in 52.3%; and at 37 weeks, in 85.4%. Pre-eclamptic toxemia/hypertension, diabetes, premature rupture of membranes, and preterm labor all had earlier appearance of PG than a comparison group. There was no delay in lung maturity in gestational diabetics or Rh isoimmunization. Infants of patients with overt diabetes with PG greater than or equal to 0.5% did not develop respiratory distress syndrome. This value appeared in 30% of diabetic patients by 35 to 36 weeks and in 76.9% by 37 weeks' gestation.

The effect of maternal glucose infusion on breathing movements in human fetuses with intrauterine growth retardation

forty-nine patients with suspected intrauterine growth retardation (IUGR) were studied under rigid experimental conditions to determine baseline fetal breathing movement (FBM) activity and the response to 90-minute maternal glucose infusion, as compared to that of normal control subjects. Patients with IUGR showed a normal amount of FBMs during maternal fasting. All groups exhibited a significant increase in FBMs after glucose was administered. During the final 60 minutes of the glucose infusion, the severe IUGR group (weight for gestational age less than the third percentile) showed less FBM activity (p less than 0.01) than the other study and control groups.

Comparison of Channelyser and Model S Plus determined platelet size measurements

A comparison has been made between Coulter Counter ZBI/Channelyser C1000 derived platelet distribution width (PDW), mean platelet volume (MPV) and platelet crit (PCT) with similar measurements generated by the Coulter counter Model S Plus. Correlations of PDW and MPV from the two systems are poor; that for PCT is acceptable. The differing results can almost certainly be attributed to physical differences in the measurement systems.

Phosphatidylglycerol determination on amniotic fluid 10,000 x g pellet in the prediction of fetal lung maturity

Phosphatidylglycerol and the lecithin/sphingomyelin (L/S) ratio were determined, and the shake test was performed, as indicators of fetal lung maturity, in more than 600 patients. A clinical review of the outcome was made in all patients who underwent delivery within 2 days after collection of amniotic fluid. Correlation was made phosphatidylglycerol, shake test, and L/S ratio results. L/S ratio had a false positive rate of 5%, and a false negative rate of 58.1%. The shake test had a false positive rate of 1.1%, and a false negative rate of 63.5%. Phosphatidylglycerol determination had a false positive rate of 1.8%, and a false negative rate of 26.9%. Phosphatidylglycerol determination is an accurate predictor of fetal lung maturity, and predicts lung immaturity more correctly than do the L/S ratio and shake test.

Fetal scalp blood pH sampling: its value in an active obstetric unit

Two hundred thirty-two patients had fetal scalp blood pH sampling performed from January 1, 1978, to September 30, 1978. Ninety-eight percent of samples were obtained for fetal heart rate (FHR) changes: 62% for variable decelerations, 10% for late and 3% for early decelerations, 10% for decreased baseline variability, and 12% for baseline rate abnormalities. Fourteen fetuses were mildly acidotic, and six were severely acidotic. All were delivered within 1 hour of the last fetal blood sample. Acidosis was significantly more frequent with late decelerations (p less than 0.05). Neonatal depression was significantly more frequent (50% incidence) only with severe fetal acidosis (p less than 0.05). Complications of fetal blood sampling occurred in 15 infants (6%), and all were minor. Based on independent review of the FHR tracings by three members of the perinatal department, it was estimated that 20 to 30 cesarean sections were avoided by determining fetal blood pH (approximately 10%).

MER-BCG (NSC-143769): immunogenicity and toxicity of single and repeated intradermal injections in dogs

Intradermal injections of MER-BCG 0.1 mg or 0.2 mg at each of 10 multiple sites, led to local granuloma formation. The nodules reached approximately 10 mm in diameter, ulcerated and were accompanied by granulomatous changes in the regional lymph nodes. Six or twelve successive treatments (each including 10 injections) at 4 week intervals produced the same histopathological lesions but no changes in hematological and blood chemical parameters or general morphology and no changes in general condition with exception of occasional weight loss in a few animals. Injection with 0.01 or 0.001 mg/site produced similar, though less severe, skin lesions but no changes in the draining lymph nodes. The immunogenicity of MER-BCG was characterized by granuloma formation, a positive skin response to old tuberculin, and a positive lymphocyte transformation to PPD tuberculin, thus indicating stimulation of cell-mediated immune responses. However, there was a decreased responsiveness to PHA and PPD with continuing treatment with MER-BCG. The decreased responsiveness and accumulation of numerous depots of antigen would suggest an "immunologic paralysis" contraindicating the administration of excessive amounts of MER-BCG during immunotherapy. A specific humoral response to the administration of MER-BCG was not detected, but an MER-BCG dose independent decrease in albumin associated with a non-specific, dose related elevation in serum IgG was observed.

Sinusoidal fetal heart rate pattern associated with alphaprodine administration

Sinusoidal fetal heart rate patterns were observed in 42.5% of a group of 40 women who had received alphaprodine (Nisentil) for relief of labor pain. Analysis showed that the pattern appeared approximately 19 minutes following alphaprodine administration and persisted for approximately 60 minutes. In a control group of 18 patients who did not receive narcotic analgesia, and intermittent sinusoidal pattern was observed in one patient. All babies with sinusoidal heart rate during labor had 1-minute Apgar scores of 7 or greater except two in the study group. Both these neonates had low Apgar scores directly associated with complications at delivery. All 5-minute Apgar scores were 7 or greater, and there were no perinatal deaths.

Evaluation of a semi-automated platelet-counting system

Coulter Electronics Ltd have produced a semi-automated platelet-counting system. Platelet-rich plasma may be obtained either by tube sedimentation or by means of the Thrombo-fuge, the latter being an instrument designed to produce accelerated sedimentation. The instrument is linear over the entire range of platelet counts, and machine reproducibility is good. Comparison of machine-rated with visual counts satisfied statistical evaluation. The technique can be handled by one operator and platelet counts can be achieved at the rate of 30 per hour by both methods although individual counts on the Thrombo-fuge may be obtained in approximately one-quarter of the time required for tube sedimentation. The throughput using the Thrombo-fuge could certainly be doubled were two sample plates supplied. Few problems were encountered during the evaluation and most could be avoided by meticulous technique. Visual counts must be performed when the sample haematocrit is greater than 50%-Discrepant counts have been obtained in patients with white cell counts exceeding 50 X 10(9)/1 and in patients with giant platelets. ESR elevation for any reason does not lead to serious discrepancy in results. The incidence of platelet clumping due to the presence of platelet agglutinins and of microclot formation due to inadequate mixing is probably much higher than is commonly thought, and certainly peripheral blood film scrutiny should never be omitted in patients with low counts. Careful examination of peripheral blood films must be combined with instrument counting for some time lest further causes of discrepant counting emerge.

Studies of the regeneration of lymphatic vessels

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The Lymphatics of the Stomach

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The Hair Tracts of the Australian Aboriginal

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