The COVID-19 herd immunity threshold is not low: A re-analysis of European data from spring of 2020

The recent publication of the Great Barrington Declaration (GBD), which calls for relaxing all public health interventions on young, healthy individuals, has brought the question of herd immunity to the forefront of COVID-19 policy discussions, and is partially based on unpublished research that suggests low herd immunity thresholds (HITs) of 10-20%. We re-evaluate these findings and correct a flawed assumption leading to COVID-19 HIT estimates of 60-80%. If policymakers were to adopt a herd immunity strategy, in which the virus is allowed to spread relatively unimpeded, we project that cumulative COVID-19 deaths would be five times higher than the initial estimates suggest. Our re-estimates of the COVID-19 HIT corroborate strong signals in the data and compelling arguments that most of the globe remains far from herd immunity, and suggest that abandoning community mitigation efforts would jeopardize the welfare of communities and integrity of healthcare systems.

Surgical access through the stoma for laparoscopic reversal of Hartmann procedures.

The rate of stoma reversal after Hartmann procedure is low, principally because of the technically demanding nature of the reversal procedure and preexisting comorbid disease frequently present in this patient group. Laparoscopic reversal of Hartmann procedure is an attractive alternative that can reduce perioperative morbidity but the feasibility of completing the procedure laparoscopically is often limited by extensive adhesion formation present after the initial open operation. We describe a technique for laparoscopic reversal of Hartmann procedure where the stoma is mobilized externally and a pneumoperitoneum established through this preexisting defect. Results for the first 7 cases show a median operative duration of 132 minutes and length of hospital stay of 6 days with no conversions. Insertion of the operating ports under direct vision and a more limited dissection to facilitate the anastomosis represents an alternative operative strategy that can be performed successfully, even in patients with comorbid disease.

Ruptured internal iliac artery aneurysm presenting as Cullen's sign.

Cullen's sign or periumbilical ecchymosis, is classically considered as an indicator of acute hemorrhagic pancreatitis or ruptured ectopic pregnancy. Internal iliac artery aneurysms are rare and are usually asymptomatic. We present a case of a contained rupture of the internal iliac artery aneurysm presenting with Cullen's sign.

Primary osteogenic sarcoma of the breast: A case report.

INTRODUCTION: Primary osteosarcoma of the breast is a rare malignant tumour. It is typically a poor prognosis tumour, which has some interesting features worthy of discussion. We report a case of primary osteosarcoma of the breast and summarise the previous medical literature to highlight several details of this unusual tumour. CASE PRESENTATION: A 66-year-old Caucasian lady presented with painless lump in her right breast. Mammography showed features of fibroadenoma with calcification and fine needle aspiration cytology was reported as showing malignant cells (C5). Wide local excision was performed and histological features were consistent with primary osteosarcoma with predominance of osteoclastic activity. Subsequent completion mastectomy was performed because of suspicion of incomplete excision. She remains disease free 8 years from her initial surgery.

Six years survival on imatinib with no disease progression after diagnosis of metastatic duodenal gastrointestinal stromal tumour: a case report.

INTRODUCTION: A duodenal Gastrointestinal Stromal Tumour (GIST) is a rare finding and until recently advanced disease had a poor prognosis. A PubMed search revealed no reports of more than five years survival of inoperable GIST on chemotherapy with WHO performance status zero. CASE PRESENTATION: A 68 year old female was diagnosed with unresectable GIST in the duodenum with metastasis to liver, pancreas and omentum in November 2001. She was commenced on imatinib mesylate (Glivec) chemotherapy. This case report was prepared from the medical records and radiology reports. She had good tolerance with stable disease. After six years her CT scan showed no disease progression and her WHO performance status was zero. CONCLUSION: This report supports the view that imatinib is a safe and effective drug in controlling disease progression in advanced metastatic GIST and plays an important role in improving the patient's quality of life.

Surgical excision of an abdominal wall granular cell tumour with Permacol(R) mesh reconstruction: a case report.

INTRODUCTION: Granular cell tumours of the abdominal wall are extremely rare: less than 10 have been reported in the worldwide medical literature. We report this interesting case, review the relevant literature on this tumour and discuss surgical abdominal wall reconstruction options. CASE PRESENTATION: A 70 year old lady presented with a left abdominal mass. This was thought to be a soft tissue sarcoma on CT imaging prior to surgical excision. En-bloc surgical resection was performed. Surgical reconstruction of the abdominal wall defect was performed using Permacol(R) mesh. Histopathological examination of the surgical specimen showed it to be a granular cell tumour. CONCLUSION: Although rare, granular cell tumours can present as an abdominal wall mass. It is important that clinicians are aware of their existence. The closure of large defects, after surgical resection of abdominal wall tumours, is a surgical challenge. We used a new biosynthetic procine mesh (Permacol(R)) which appeared to work well in this situation.

The fourteen-day rule and colorectal cancer.

OBJECTIVE: To examine the effect of the fourteen-day rule on the colorectal service of a district general hospital. METHODS: Prospective audit of all patients referred by general practitioners to the colorectal service of a district general hospital serving a population of approximately 300,000 people. The main outcome measures were: (i) mean interval in days from referral to first clinic appointment; (ii) first clinic appointment to diagnosis; and (iii) overall interval from referral to diagnosis. RESULTS: There was a change in the referral pattern with greater numbers of 'fourteen-day rule' and urgent referrals than expected (P < 0.001). The mean time interval from referral to diagnosis was reduced (P < 0.01). This was due to a reduction in the wait for a first clinic appointment (P < 0.01). The wait between first appointment and diagnosis was unchanged (P < 0.05). Waiting times for patients referred as 'routine' or whose GPs did not specify a priority also improved. CONCLUSIONS: The 'fourteen-day rule' with respect to colorectal cancer has reduced waiting times for a first appointment to see a specialist. Further improvements will require additional resources to reduce the delay for investigations. The effect on long-term survival remains to be seen.