Social Disadvantage and Multimorbidity Including Oral Conditions in the United States

Existing studies on multimorbidity have largely excluded oral diseases in multimorbidity prevalence estimates. The reason behind this is somewhat unclear, as chronic oral conditions are highly prevalent, affecting over half the global population. To address this gap, we examined the relationship between social disadvantage and multimorbidity, stratifying by the inclusion and exclusion of oral conditions. For participants aged 30 y and over (n = 3,693), cross-sectional analysis was carried out using the US National Health and Nutrition Survey (2013-2014). Multimorbidity was defined as having 2 or more chronic conditions. Five medical conditions were examined: diabetes, asthma, arthritis, cardiovascular disease, and depression, as well as 4 oral health conditions: caries, periodontal disease, number of teeth, and edentulousness. Education and income poverty ratio were selected as measures of social disadvantage. Multimorbidity prevalence estimates according to social disadvantage were analyzed on an absolute and relative scale using inverse probability treatment weighting (IPTW), adjusting for age, sex, and ethnicity. The inclusion of oral health conditions in the assessment of multimorbidity increased the overall prevalence of multimorbidity from 20.8% to 53.4%. Findings from IPTW analysis demonstrated clear social gradients for multimorbidity estimates stratified by the exclusion of oral conditions. Upon inclusion of oral conditions, the prevalence of multimorbidity was higher across all social groups for both education and income. Stratifying by the inclusion of oral conditions, the mean probability of multimorbidity was 27% (95% confidence interval [CI], 23%-30%) higher in the low-education group compared to the high-education group. Similarly, the mean probability of multimorbidity was 44% (95% CI, 40%-48%) higher in the low-income group. On a relative scale, low education was associated with a 1.52 times (95% CI, 1.44-1.61) higher prevalence of multimorbidity compared to high education. Low income was associated with a 2.18 (95% CI, 1.99-2.39) higher prevalence of multimorbidity. This novel study strongly supports the impact of chronic oral conditions on multimorbidity prevalence estimates.

Characterizing SARS-CoV-2 Transcription of Subgenomic and Genomic RNAs During Early Human Infection Using Multiplexed Droplet Digital Polymerase Chain Reaction

BACKGROUND

Control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission requires understanding SARS-CoV-2 replication dynamics.

METHODS

We developed a multiplexed droplet digital polymerase chain reaction (ddPCR) assay to quantify SARS-CoV-2 subgenomic RNAs (sgRNAs), which are only produced during active viral replication, and discriminate them from genomic RNAs (gRNAs). We applied the assay to specimens from 144 people with single nasopharyngeal samples and 27 people with >1 sample. Results were compared to quantitative PCR (qPCR) and viral culture.

RESULTS

sgRNAs were quantifiable across a range of qPCR cycle threshold (Ct) values and correlated with Ct values. The ratio sgRNA:gRNA was stable across a wide range of Ct values, whereas adjusted amounts of N sgRNA to a human housekeeping gene declined with higher Ct values. Adjusted sgRNA and gRNA amounts were quantifiable in culture-negative samples, although levels were significantly lower than in culture-positive samples. Daily testing of 6 persons revealed that sgRNA is concordant with culture results during the first week of infection but may be discordant with culture later in infection. sgRNA:gRNA is constant during infection despite changes in viral culture.

CONCLUSIONS

Ct values from qPCR correlate with active viral replication. More work is needed to understand why some cultures are negative despite presence of sgRNA.

Longitudinal Analysis of SARS-CoV-2 Vaccine Breakthrough Infections Reveals Limited Infectious Virus Shedding and Restricted Tissue Distribution

Background

The global effort to vaccinate people against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during an ongoing pandemic has raised questions about how vaccine breakthrough infections compare with infections in immunologically naive individuals and the potential for vaccinated individuals to transmit the virus.

Methods

We examined viral dynamics and infectious virus shedding through daily longitudinal sampling in 23 adults infected with SARS-CoV-2 at varying stages of vaccination, including 6 fully vaccinated individuals.

Results

The durations of both infectious virus shedding and symptoms were significantly reduced in vaccinated individuals compared with unvaccinated individuals. We also observed that breakthrough infections are associated with strong tissue compartmentalization and are only detectable in saliva in some cases.

Conclusions

Vaccination shortens the duration of time of high transmission potential, minimizes symptom duration, and may restrict tissue dissemination.

Mitigation of SARS-CoV-2 transmission at a large public university

In Fall 2020, universities saw extensive transmission of SARS-CoV-2 among their populations, threatening health of the university and surrounding communities, and viability of in-person instruction. Here we report a case study at the University of Illinois at Urbana-Champaign, where a multimodal “SHIELD: Target, Test, and Tell” program, with other non-pharmaceutical interventions, was employed to keep classrooms and laboratories open. The program included epidemiological modeling and surveillance, fast/frequent testing using a novel low-cost and scalable saliva-based RT-qPCR assay for SARS-CoV-2 that bypasses RNA extraction, called covidSHIELD, and digital tools for communication and compliance. In Fall 2020, we performed >1,000,000 covidSHIELD tests, positivity rates remained low, we had zero COVID-19-related hospitalizations or deaths amongst our university community, and mortality in the surrounding Champaign County was reduced more than 4-fold relative to expected. This case study shows that fast/frequent testing and other interventions mitigated transmission of SARS-CoV-2 at a large public university.

Mitigation of SARS-CoV-2 transmission at a large public university

In Fall 2020, universities saw extensive transmission of SARS-CoV-2 among their populations, threatening health of the university and surrounding communities, and viability of in-person instruction. Here we report a case study at the University of Illinois at Urbana-Champaign, where a multimodal “SHIELD: Target, Test, and Tell” program, with other non-pharmaceutical interventions, was employed to keep classrooms and laboratories open. The program included epidemiological modeling and surveillance, fast/frequent testing using a novel low-cost and scalable saliva-based RT-qPCR assay for SARS-CoV-2 that bypasses RNA extraction, called covidSHIELD, and digital tools for communication and compliance. In Fall 2020, we performed >1,000,000 covidSHIELD tests, positivity rates remained low, we had zero COVID-19-related hospitalizations or deaths amongst our university community, and mortality in the surrounding Champaign County was reduced more than 4-fold relative to expected. This case study shows that fast/frequent testing and other interventions mitigated transmission of SARS-CoV-2 at a large public university.

Safely opening university campuses has been a major challenge during the COVID-19 pandemic. Here, the authors describe a program of public health measures employed at a university in the United States which, combined with other non-pharmaceutical interventions, allowed the university to stay open in fall 2020 with limited evidence of transmission.

POS1421 AROMATASE INHIBITORS AND SKELETAL HEALTH – NATURAL HISTORY AND INTERVENTIONAL EPIDEMIOLOGY

Background

Breast cancer remains the most common cancer diagnosed in women worldwide. Aromatase inhibitors (AI) are employed for hormone sensitive disease in mainly postmenopausal women. AI related bone loss (AIBL) is a known complication; although data regarding the natural history in the real-world, long-term outcomes and the role of bone active therapy in fracture prevention is sparse.

Objectives

Our aim was to determine the real-world impact of AIBL and whether bone sparing therapy utilising standard risk stratification model is sufficient for fracture prevention.

Methods

We undertook a longitudinal study of patients prescribed AI for breast cancer over a seven-year period at our university teaching hospital. All the data was recorded electronically with full access to demographics, disease parameters, investigations and drug management. DEXA scans performed prior to initiation of AI were compared with subsequent imaging over a mean follow up of 3 years. Outcome data for cancer and all fractures was collected. Statistical analysis was done to investigate significant relationships amongst the variables of interest.

Results

1001 women were identified during the study period. The mean age of the cohort was 64 years (range 29-93). 929 (93%) were Caucasian, 57 (6%) were Asian and 15 (1%) were Afro-Caribbean. 723 women (72%) were diagnosed with invasive ductal carcinoma and 863 women (86%) were postmenopausal. At diagnosis, 428 women (43%) had node positive disease and 35 women (4%) had metastases. 91 women (9%) had sustained fractures prior to their breast cancer diagnosis.

All women had a baseline DEXA: 496 (49.6%) had osteopenia, 151 (15%) had osteoporosis and 354 (35.4%) had a normal result. 478 (48%) of women had a repeat scan available. Overall, there was a decline (from a mean of 0.888 g/cm2 to 0.858 g/cm2, p<0.0001) in left neck of femur (LNOF) bone mineral density (BMD) over time (mean of 3 years, with a range of 1-6).

334 (33%) were prescribed bone active therapy with 276 women (83%) given oral bisphosphonates. This group had an improvement in BMD by 0.4% (LNOF mean BMD of 0.785 g/cm2 at baseline compared to LNOF mean BMD of 0.788 at repeat DEXA, p=0.82).

Women who were not offered any treatment (n=667, 66%), showed a significant decline in bone density with the decline being -5%. (LNOF mean BMD of 0.939 g/cm2 at baseline compared to LNOF mean BMD of 0.888 g/cm2 at repeat DEXA, p< 0.0001).

The rate of fractures remained the same between the treatment (19 fractures, 5.67%) and non-treatment group (38 fractures, 5.70%)

Conclusion

Our study provides long term data for AIBL and confirms a significant decline in BMD over seven years. It confirms that bone sparing therapy is effective in reducing the pace of decline in BMD. However standard risk stratification model such as FRAX based intervention thresholds in mainly those with WHO defined osteoporosis (T ≤-2.5) is ineffective in fracture prevention in keeping with prior literature. Since our study period overlaps with publication of newer guidelines recommending different T score-based risk model, further studies are required to confirm their utility.

References

[1]https://www.wcrf.org/dietandcancer/worldwide-cancer-data/. Date accessed: 26.01.2022

[2]R. Coleman, J.J. Body, M. Aapro, et al., Bone health in cancer patients: ESMO clinical practice guidelines, Ann. Oncol. 25 (Suppl 3) (2014) iii124–iii137.

[3]E. Amir, B. Seruga, S. Niraula, et al., Toxicity of adjuvant endocrine therapy in postmenopausal breast cancer patients: a systematic review and meta-analysis, J. Natl. Cancer Inst. 103 (2011) 1299–1309.

Disclosure of Interests

None declared

OP0244 AROMATASE INHIBITORS AND FRACTURE PREVENTION – DO NEW GUIDELINES WORK IN REAL WORLD?

Background

2,261,419 women were diagnosed with breast cancer worldwide in 2020. For postmenopausal women with hormone sensitive disease, aromatase inhibitors (AI) are recommended for their mortality benefit. However, AI bone loss (AIBL) is a recognised adverse event with resultant increase in fracture risk. In 2017, a consensus statement of 7 international bone and cancer societies was published proposing an algorithm based on clinical risk factors and different bone mineral density (BMD) threshold for bone active therapeutic intervention.

Objectives

To determine the real-world impact of the 2017 consensus guidelines on AIBL and whether bone sparing therapy utilising proposed risk stratification model is effective in fracture prevention.

Methods

Over a 7-year study period, 1001 women were prescribed AI at our university teaching hospital. The new guidelines were adopted in July 2017. We split the participants in two groups: 361 (36%) women had commenced their AI prior to the adoption of guidelines and 640 (64%) were in the post implementation group.

First group were offered bone active treatment based on NOS 2009 guidelines whereas the second group followed the 2017 consensus guidelines. Women with osteoporosis were all offered treatment, however the difference in guideline is pertinent to osteopenia and we compared the results of that group.

Results

1001 women were included. Mean age was 64 years (range 29-93). 929 (93%) were Caucasian, 57 (6%) were Asian and 15 (1%) were Afro-Caribbean. 723 women (72%) had invasive ductal carcinoma and 863 women (86%) were postmenopausal. At diagnosis, 428 women (43%) had node positive disease and 35 women (4%) had metastases. 91 women (9%) had sustained fractures prior to their cancer diagnosis.

276 women (28%) were offered oral bisphosphonates based on DEXA result, with 58 (6%) offered parenteral therapy.

First group: 361 women had a baseline DEXA with a mean left neck of femur (LNOF) BMD of 0.888 g/cm2 (range 0.552-1.222). 143 (40%) women had a normal DEXA, 174 (48%) had osteopenia and 44 (12%) had osteoporosis.

Of the women with osteopenia, 44 (25%) women were offered treatment and 33 women had a repeat DEXA after a mean of 4 years. In the treatment group, LNOF mean BMD remained relatively unchanged from 0.814 g/cm2 to 0.812 g/cm2 at the repeat DEXA (p= 0.94).

Of the 174 women with osteopenia, 22 (13%) women had a fracture.

Second group: 640 women had a baseline DEXA with a mean LNOF BMD of 0.888 g/cm2 (range 0.512-1.390). 216 (33%) women were normal, 322(50%) had osteopenia and 107 (17%) had osteoporosis.

Of the women with osteopenia, 127 (39%) women were offered treatment and 56 women had a repeat DEXA after a mean of 3 years. In the treatment group, LNOF mean BMD remained relatively unchanged from 0.822 g/cm2 to 0.829 g/cm2 at the repeat DEXA (p= 0.6169).

Of the 322 women with osteopenia, 8 (2.5%) women had a fracture.

Conclusion

Our study provides real world evidence of the success of 2017 consensus statement in lowering fracture risk. Though there has been data for positive impact on BMD decline with this approach, evidence for fracture prevention has been limited. This study showcases the success of lowering bone active therapy threshold employing alternative risk modelling strategy for women with breast cancer commenced on AI. A significant reduction in fractures pre (13%) and post guidelines change (2.5%) was demonstrated (absolute risk reduction of 10.5%) which has implications for healthcare systems worldwide as we have demonstrated this approach can reduce morbidity.

References

[1]https://www.wcrf.org/dietandcancer/worldwide-cancer-data/. Accessed: 26.01.2022.

[2]Reid DM, Doughty J, Eastell R, et al. Guidance for the management of breast cancer treatment-induced bone loss: a consensus position statement from a UK Expert Group. Cancer Treat Rev. 2008;34 Suppl 1:S3-S18.

[3]Hadji P, Aapro MS, Body JJ, et al. Management of Aromatase Inhibitor-Associated Bone Loss (AIBL) in postmenopausal women with hormone sensitive breast cancer: Joint position statement of the IOF, CABS, ECTS, IEG, ESCEO IMS, and SIOG. J Bone Oncol. 2017;7:1-12.

Disclosure of Interests

None declared

Daily longitudinal sampling of SARS-CoV-2 infection reveals substantial heterogeneity in infectiousness

The dynamics of SARS-CoV-2 replication and shedding in humans remain poorly understood. We captured the dynamics of infectious virus and viral RNA shedding during acute infection through daily longitudinal sampling of 60 individuals for up to 14 days. By fitting mechanistic models, we directly estimated viral expansion and clearance rates and overall infectiousness for each individual. Significant person-to-person variation in infectious virus shedding suggests that individual-level heterogeneity in viral dynamics contributes to 'superspreading'. Viral genome loads often peaked days earlier in saliva than in nasal swabs, indicating strong tissue compartmentalization and suggesting that saliva may serve as a superior sampling site for early detection of infection. Viral loads and clearance kinetics of Alpha (B.1.1.7) and previously circulating non-variant-of-concern viruses were mostly indistinguishable, indicating that the enhanced transmissibility of this variant cannot be explained simply by higher viral loads or delayed clearance. These results provide a high-resolution portrait of SARS-CoV-2 infection dynamics and implicate individual-level heterogeneity in infectiousness in superspreading.

Limitations of molecular and antigen test performance for SARS-CoV-2 in symptomatic and asymptomatic COVID-19 contacts

OBJECTIVES

COVID-19 has brought unprecedented attention to the crucial role of diagnostics in pandemic control. We compared SARS-CoV-2 test performance by sample type and modality in close contacts of SARS-CoV-2 cases.

METHODS

Close contacts of SARS-CoV-2 positive individuals were enrolled after informed consent. Clinician-collected nasopharyngeal (NP) swabs in viral transport media (VTM) were tested with a nucleic acid test (NAT). NP VTM and self-collected passive drool were tested using the PerkinElmer real-time reverse transcription PCR (RT-PCR) assay. For the first 4 months of study, mid-turbinate swabs were tested using the BD Veritor rapid antigen test. NAT positive NP samples were tested for infectivity using a VeroE6TMPRSS2 cell culture model.

RESULTS

Between November 17, 2020, and October 1, 2021, 235 close contacts of SARS-CoV-2 cases were recruited, including 95 with symptoms (82% symptomatic for < 5 days) and 140 asymptomatic individuals. NP swab reference tests were positive for 53 (22.6%) participants; 24/50 (48%) were culture positive. PerkinElmer testing of NP and saliva samples identified an additional 28 (11.9%) SARS-CoV-2 cases who tested negative by clinical NAT. Antigen tests performed for 99 close contacts showed 83% positive percent agreement (PPA) with reference NAT among early symptomatic persons, but 18% PPA in others; antigen tests in 8 of 11 (72.7%) culture-positive participants were positive.

CONCLUSIONS

Contacts of SARS-CoV-2 cases may be falsely negative early after contact, which more sensitive platforms may identify. Repeat or serial SARS-CoV-2 testing with both antigen and molecular assays may be warranted for individuals with high pretest probability for infection.

Adolescent girls’ recommendations for designing Human Papillomavirus Vaccination Program in Pakistan

 

In Pakistan, cervical cancer is the third most frequent cancer among women. Most cases are caused by sexually-acquired infection with human papillomaviruses (HPV). Vaccination of adolescent girls against HPV significantly reduces the incidence of cervical cancer. HPV vaccination is available in Pakistan, but plans to develop a HPV vaccination program are currently at a very early stage. We conducted a formative study to explore adolescent girls' perspectives on HPV and cervical cancer, and collected their recommendations for implementing an HPV vaccination program. We conducted qualitative focus group discussions (FGDs), with unmarried adolescent girls aged 16-19 years, residing in Karachi. We conducted four FGDs with 12 participants each. The topic guide assessed i) girls' knowledge of cervical cancer and HPV vaccination, ii) vaccination decision-making dynamics within families, and iii) factors girls would consider essential for the successful implementation of HPV vaccination program. Overall, participants displayed a positive attitude towards the HPV vaccine. However, many basic concepts related to female reproductive health were unfamiliar to them. Female relatives were indicated as girls' preferred point of contact for discussions on HPV and cervical cancer, but fathers were portrayed as the definitive decision-making authority on vaccination. Girls gave critical input for the development of a HPV vaccination program. Eligible girls should be recruited through individual household visits and the vaccine should be administered at community-based camps, which would ensure both good accessibility and a large outreach. A solid foundation of trust between girls' families, program managers, and other stakeholders emerged as a key asset for the program's success. Adolescents demonstrated great capacity and shared recommendations for a future program's acceptability. Integrating their perspectives will be essential to design an effective program in local context.

Key messages

Adolescent girls’ perspectives should be incorporated to develop context-specific recommendations for the implementation of a HPV vaccination program. Community-based camps and household visits by adolescent girls to recruit the target population could potentially increase program penetration among communities.

Longitudinal Assessment of Diagnostic Test Performance Over the Course of Acute SARS-CoV-2 Infection

BACKGROUND

Serial screening is critical for restricting spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by facilitating timely identification of infected individuals to interrupt transmission. Variation in sensitivity of different diagnostic tests at different stages of infection has not been well documented.

METHODS

In a longitudinal study of 43 adults newly infected with SARS-CoV-2, all provided daily saliva and nasal swabs for quantitative reverse transcription polymerase chain reaction (RT-qPCR), Quidel SARS Sofia antigen fluorescent immunoassay (FIA), and live virus culture.

RESULTS

Both RT-qPCR and Quidel SARS Sofia antigen FIA peaked in sensitivity during the period in which live virus was detected in nasal swabs, but sensitivity of RT-qPCR tests rose more rapidly prior to this period. We also found that serial testing multiple times per week increases the sensitivity of antigen tests.

CONCLUSIONS

RT-qPCR tests are more effective than antigen tests at identifying infected individuals prior to or early during the infectious period and thus for minimizing forward transmission (given timely results reporting). All tests showed >98% sensitivity for identifying infected individuals if used at least every 3 days. Daily screening using antigen tests can achieve approximately 90% sensitivity for identifying infected individuals while they are viral culture positive.

Longitudinal analysis of SARS-CoV-2 vaccine breakthrough infections reveal limited infectious virus shedding and restricted tissue distribution

The global effort to vaccinate people against SARS-CoV-2 in the midst of an ongoing pandemic has raised questions about the nature of vaccine breakthrough infections and the potential for vaccinated individuals to transmit the virus. These questions have become even more urgent as new variants of concern with enhanced transmissibility, such as Delta, continue to emerge. To shed light on how vaccine breakthrough infections compare with infections in immunologically naive individuals, we examined viral dynamics and infectious virus shedding through daily longitudinal sampling in a small cohort of adults infected with SARS-CoV-2 at varying stages of vaccination. The durations of both infectious virus shedding and symptoms were significantly reduced in vaccinated individuals compared with unvaccinated individuals. We also observed that breakthrough infections are associated with strong tissue compartmentalization and are only detectable in saliva in some cases. These data indicate that vaccination shortens the duration of time of high transmission potential, minimizes symptom duration, and may restrict tissue dissemination.

Daily sampling of early SARS-CoV-2 infection reveals substantial heterogeneity in infectiousness

The dynamics of SARS-CoV-2 replication and shedding in humans remain poorly understood. We captured the dynamics of infectious virus and viral RNA shedding during acute infection through daily longitudinal sampling of 60 individuals for up to 14 days. By fitting mechanistic models, we directly estimate viral reproduction and clearance rates, and overall infectiousness for each individual. Significant person-to-person variation in infectious virus shedding suggests that individual-level heterogeneity in viral dynamics contributes to superspreading. Viral genome load often peaked days earlier in saliva than in nasal swabs, indicating strong compartmentalization and suggesting that saliva may serve as a superior sampling site for early detection of infection. Viral loads and clearance kinetics of B.1.1.7 and non-B.1.1.7 viruses in nasal swabs were indistinguishable, however B.1.1.7 exhibited a significantly slower pre-peak growth rate in saliva. These results provide a high-resolution portrait of SARS-CoV-2 infection dynamics and implicate individual-level heterogeneity in infectiousness in superspreading.

POS0227 SHOULD ALL PATIENTS TRIAL SUBCUTANEOUS METHOTREXATE PRIOR TO COMMENCING BIOLOGIC THERAPY – A REAL WORLD STUDY

Background:

Methotrexate (MTX) is the bed rock of inflammatory arthritis management. However intolerance is a major limiting factor for drug optimisation and retention. There is data to suggest that subcutaneous (SC) MTX is tolerated better and is now being recommended in several guidelines including ACR’s. It is less clear though whether this strategy is effective in those where oral preparation is inefficacious and its potential to avoid escalation to biologic therapy.

Objectives:

Our aim was to analyse the reasons for switching to SC formulation in a real world setting, clinical outcomes achieved and proportion requiring biologic prescription.

Methods:

We undertook a retrospective survey of all patients prescribed SC MTX in a large university teaching hospital between 1983 and Apr 2019. We had access to full patient records including details on co-morbidities, drugs and disease management. We analysed demographics, reasons for SC MTX initiation, clinical outcomes and impact on biologic prescription.

Results:

352 patients were identified during the study period. The mean age of the cohort was 54 yrs (3-87). 192 (70%) were women. 260 (74%) were Caucasian, 64 (18%) Asian, 21 (6%) Afro-Caribbean and remaining of other ethnicity. Two most common diagnoses were RA [n=243 (69%)] and pSpA [n=66 (18%)]. Average disease duration was 74 months (11-324) with mean of three comorbidities (0-11).

284 (80%) had switched from oral to SC MTX. 137 (49%) stopped oral MTX due to side effects. Mean duration of oral MTX prior to switching was 26 months (0.25-167). Follow up period for SC MTX ranged from two to 132 months (mean 29) until the data cut-off date of Apr 2019. 103 (29%) patients progressed to biologic therapy.

Amongst RA patients, DAS28 improved from mean 4.16 (0.63-8.06) to 2.83 (0.14-7.32) following the switch. pSpA cohort’s mean TJC and SJC improved from mean seven (0-42) and two (0-26) to two (0-25) and one (0-6) respectively.

Conclusion:

Our study confirms that SC MTX is an effective solution irrespective of whether oral MTX is inefficacious or intolerable. This applies to people with both RA and pSpA. In accordance with prior published data, our findings support the utility of SC MTX for those intolerant of enteral option. Additionally, it shows that even in instances where oral MTX was ineffective, a switch to SC formulation achieved low disease activity despite multi-morbidity, long disease course and protracted oral MTX exposure. This intervention also prevented over two-thirds of patients progressing to biologic therapy with significant financial savings. SC MTX therefore remains a durable strategy with excellent disease outcomes and confers substantial economic benefits to healthcare.

Disclosure of Interests:

None declared

Longitudinal assessment of diagnostic test performance over the course of acute SARS-CoV-2 infection

What is already known about this topic?

Diagnostic tests and sample types for SARS-CoV-2 vary in sensitivity across the infection period.

What is added by this report?

We show that both RTqPCR (from nasal swab and saliva) and the Quidel SARS Sofia FIA rapid antigen tests peak in sensitivity during the period in which live virus can be detected in nasal swabs, but that the sensitivity of RTqPCR tests rises more rapidly in the pre-infectious period. We also use empirical data to estimate the sensitivities of RTqPCR and antigen tests as a function of testing frequency.

What are the implications for public health practice?

RTqPCR tests will be more effective than rapid antigen tests at identifying infected individuals prior to or early during the infectious period and thus for minimizing forward transmission (provided results reporting is timely). All modalities, including rapid antigen tests, showed >94% sensitivity to detect infection if used at least twice per week. Regular surveillance/screening using rapid antigen tests 2-3 times per week can be an effective strategy to achieve high sensitivity (>95%) for identifying infected individuals.

Real-time immunization trends in under-2 children in Pakistan: insights from big data analysis

Background

Despite the provision of free-of-cost vaccines in Pakistan, fully immunized child (FIC) coverage in Sindh province remains low at 49%. In 2012, we developed and piloted the Zindagi Mehfooz (Safe Life; ZM) Digital Immunization Registry, an Android-based platform that enables vaccinators to enroll and track child level immunization data of children in the catchment population. In 2017, ZM was scaled-up across Sindh province and is currently being used by 2,284 vaccinators across 1,526 facilities serving &gt;48 million (m) population.

Methods

All children under-2 years of age visiting EPI centers are enrolled. At enrollment, caregiver and child bio-data and child immunization history are recorded, and the child is provided with a unique Quick Response (QR) code for identification. For follow-up immunization visits, 3 SMS reminders are sent to caregivers, and upon immunization, child history is retrieved by scanning the QR code and vaccination record updated. ZM allows real-time access to data and generation of monitoring reports. Data from ZM was used to calculate coverage rates, timeliness, and trends for immunization coverage in Sindh.

Results

From Oct'17 to Dec'19, more than 2.4m children and 0.8m women were enrolled in the Registry, while &gt;17m immunizations were administered. The FIC coverage in 12-23 months old children has increased from 49% (at baseline) to 57% for children enrolled in ZM. Additionally, pentavalent-3 coverage increased from 59% to 68%.

Discussion

ZM demonstrates the potential of DIRs to improve immunization outcomes within low-resource settings by enabling better child tracking and a higher retention rate. Additionally, the big dataset provides the opportunity to identify real-time trends and provides actionable data for evidence-based decision making.

Key messages

ZM Immunization Registry has strengthened the current EPI program through increased FIC coverage and timeliness through better tracking of children and increased retention. Big Data from ZM can be used to analyze immunization trends of global relevance, and guide strategic policy decisions for improving immunization coverage and equity, based on actionable data insights.

Using mobile immunization vans to cover under-served populations in hard-to-reach areas

Background

In Pakistan, only 66% of children receive their basic vaccinations. However, the figure masks significant inequalities in vaccine coverage between urban and rural residences, slums and areas distantly located from EPI centers. Frequent outbreaks of vaccine-preventable diseases such as polio and measles, in urban cities like Karachi, signal the need for expanding vaccine services to underserved areas. In Apr'19, we introduced the Mobile Immunization Van initiative in Karachi in collaboration with EPI Sindh. Currently, two vans are deployed in hard-to-reach areas and slums to immunize under-2 children for routine vaccines.

Methods

Before the van visit, mobilization efforts are conducted in targeted areas to encourage caretakers to bring their child for vaccination. On the day of visit, the van is parked at a central location, and announcements are played on a loudspeaker to attract caregivers. All vaccinations are administered in the van, and entries are recorded in Government's Digital Immunization Registry along with GIS coordinates of immunized children. The data is then automatically transferred on to a web-dashboard for analysis and tracking.

Results

From Apr'19 to Jan'20, the vans have vaccinated 2,867 children, out of which 50% had never been immunized prior to the van visit. Of those who received their follow-up vaccines from the van, 80% were at least 4 weeks beyond from their vaccine due date. GIS analysis of van data confirmed that immunizations were conducted in slums, and areas distantly located from EPI centers. Moreover, compared to government outreach activity, proportion of BCG, Penta3 and Measles1 administrations in slums was higher through the vans by 5%, 6%, and 4% respectively.

Conclusions

The vans provide an opportunity for immunizing never-vaccinated children and children defaulting on their vaccine schedule, from the most vulnerable geographies, while simultaneously enrolling them in the Government's EPI Program for effective tracking.

Key messages

The mobile vans help achieve universal immunization coverage through provision of vaccine services in slum and rural hard-to-reach areas with limited access to government-provided services. The mobile vans help vaccinate and capture never-immunized children into the Government’s EPI records, reducing the number of children missed through routine services.

Level III dissection in locally advanced breast cancer following neoadjuvant chemotherapy: a retrospective study

INTRODUCTION

Breast cancer is the most common female cancer in India, and 30-60% of patients present with locally advanced breast cancer. Level III clearance is routinely performed in India in locally advanced breast cancer following neoadjuvant chemotherapy, even in clinical complete response. We analysed our data of patients with locally advanced breast cancer post-neoadjuvant chemotherapy who have undergone level III clearance to identify any subgroup in which level III dissection can be avoided.

MATERIAL AND METHODS

This is a retrospective study of female patients with locally advanced breast cancer who received neoadjuvant chemotherapy and underwent breast surgery including level III nodal clearance between June 2016 and May 2018. Data collected included age, menopausal status, TNM stage at presentation, grade, estrogen, progesterone, human epidermal growth factor receptor 2 status, response to treatment, post-chemotherapy stage and final histopathology. Uni- and multivariate analysis was undertaken.

RESULTS

Data from 200 patients was analysed. The level III positivity rate was 15.5%. The clinical complete response rate was 43%, of which 41% had pathological complete response. A significant association was present between level III node positivity and pathological T stage (p=0.03). No association was seen between level III positivity and any other studied variables. In the subset of patients with cT3N1 and cT2N2, level III positivity was seen in only 3/49 (6.1%) and 1/31 (3%), respectively.

CONCLUSION

Level III positivity rate is high and so cannot be avoided in locally advanced breast cancer following neoadjuvant chemotherapy. None of the preoperative factors predict for level III positivity. Level III positivity in cT3N1 and cT2N2 is low and these subgroups require further studies.

α-PD-1 therapy elevates Treg/Th balance and increases tumor cell pSmad3 that are both targeted by α-TGFβ antibody to promote durable rejection and immunity in squamous cell carcinomas

BACKGROUND

Checkpoint blockade immunotherapy has improved metastatic cancer patient survival, but response rates remain low. There is an unmet need to identify mechanisms and tools to circumvent resistance. In human patients, responses to checkpoint blockade therapy correlate with tumor mutation load, and intrinsic resistance associates with pre-treatment signatures of epithelial mesenchymal transition (EMT), immunosuppression, macrophage chemotaxis and TGFβ signaling.

METHODS

To facilitate studies on mechanisms of squamous cell carcinoma (SCC) evasion of checkpoint blockade immunotherapy, we sought to develop a novel panel of murine syngeneic SCC lines reflecting the heterogeneity of human cancer and its responses to immunotherapy. We characterized six Kras-driven cutaneous SCC lines with a range of mutation loads. Following implantation into syngeneic FVB mice, we examined multiple tumor responses to α-PD-1, α-TGFβ or combinatorial therapy, including tumor growth rate and regression, tumor immune cell composition, acquired tumor immunity, and the role of cytotoxic T cells and Tregs in immunotherapy responses.

RESULTS

We show that α-PD-1 therapy is ineffective in establishing complete regression (CR) of tumors in all six SCC lines, but causes partial tumor growth inhibition of two lines with the highest mutations loads, CCK168 and CCK169. α-TGFβ monotherapy results in 20% CR and 10% CR of established CCK168 and CCK169 tumors respectively, together with acquisition of long-term anti-tumor immunity. α-PD-1 synergizes with α-TGFβ, increasing CR rates to 60% (CCK168) and 20% (CCK169). α-PD-1 therapy enhances CD4 + Treg/CD4 + Th ratios and increases tumor cell pSmad3 expression in CCK168 SCCs, whereas α-TGFβ antibody administration attenuates these effects. We show that α-TGFβ acts in part through suppressing immunosuppressive Tregs induced by α-PD-1, that limit the anti-tumor activity of α-PD-1 monotherapy. Additionally, in vitro and in vivo, α-TGFβ acts directly on the tumor cell to attenuate EMT, to activate a program of gene expression that stimulates immuno-surveillance, including up regulation of genes encoding the tumor cell antigen presentation machinery.

CONCLUSIONS

We show that α-PD-1 not only initiates a tumor rejection program, but can induce a competing TGFβ-driven immuno-suppressive program. We identify new opportunities for α-PD-1/α-TGFβ combinatorial treatment of SCCs especially those with a high mutation load, high CD4+ T cell content and pSmad3 signaling. Our data form the basis for clinical trial of α-TGFβ/α-PD-1 combination therapy (NCT02947165).

α-PD-1 therapy elevates Treg/Th balance and increases tumor cell pSmad3 that are both targeted by α-TGFβ antibody to promote durable rejection and immunity in squamous cell carcinomas

BACKGROUND

Checkpoint blockade immunotherapy has improved metastatic cancer patient survival, but response rates remain low. There is an unmet need to identify mechanisms and tools to circumvent resistance. In human patients, responses to checkpoint blockade therapy correlate with tumor mutation load, and intrinsic resistance associates with pre-treatment signatures of epithelial mesenchymal transition (EMT), immunosuppression, macrophage chemotaxis and TGFβ signaling.

METHODS

To facilitate studies on mechanisms of squamous cell carcinoma (SCC) evasion of checkpoint blockade immunotherapy, we sought to develop a novel panel of murine syngeneic SCC lines reflecting the heterogeneity of human cancer and its responses to immunotherapy. We characterized six Kras-driven cutaneous SCC lines with a range of mutation loads. Following implantation into syngeneic FVB mice, we examined multiple tumor responses to α-PD-1, α-TGFβ or combinatorial therapy, including tumor growth rate and regression, tumor immune cell composition, acquired tumor immunity, and the role of cytotoxic T cells and Tregs in immunotherapy responses.

RESULTS

We show that α-PD-1 therapy is ineffective in establishing complete regression (CR) of tumors in all six SCC lines, but causes partial tumor growth inhibition of two lines with the highest mutations loads, CCK168 and CCK169. α-TGFβ monotherapy results in 20% CR and 10% CR of established CCK168 and CCK169 tumors respectively, together with acquisition of long-term anti-tumor immunity. α-PD-1 synergizes with α-TGFβ, increasing CR rates to 60% (CCK168) and 20% (CCK169). α-PD-1 therapy enhances CD4 + Treg/CD4 + Th ratios and increases tumor cell pSmad3 expression in CCK168 SCCs, whereas α-TGFβ antibody administration attenuates these effects. We show that α-TGFβ acts in part through suppressing immunosuppressive Tregs induced by α-PD-1, that limit the anti-tumor activity of α-PD-1 monotherapy. Additionally, in vitro and in vivo, α-TGFβ acts directly on the tumor cell to attenuate EMT, to activate a program of gene expression that stimulates immuno-surveillance, including up regulation of genes encoding the tumor cell antigen presentation machinery.

CONCLUSIONS

We show that α-PD-1 not only initiates a tumor rejection program, but can induce a competing TGFβ-driven immuno-suppressive program. We identify new opportunities for α-PD-1/α-TGFβ combinatorial treatment of SCCs especially those with a high mutation load, high CD4+ T cell content and pSmad3 signaling. Our data form the basis for clinical trial of α-TGFβ/α-PD-1 combination therapy (NCT02947165).

Improvement in lipids after switch to boosted atazanavir or darunavir in children/adolescents with perinatally acquired HIV on older protease inhibitors: results from the Pediatric HIV/AIDS Cohort Study

OBJECTIVES

Dyslipidaemia is common in perinatally HIV-infected (PHIV) youth receiving protease inhibitors (PIs). Few studies have evaluated longitudinal lipid changes in PHIV youth after switch to newer PIs.

METHODS

We compared longitudinal changes in fasting lipids [total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and TC:HDL-C ratio] in PHIV youth enrolled in the Pediatric HIV/AIDS Cohort Study (PHACS) Adolescent Master Protocol (AMP) study who switched to atazanavir/ritonavir (ATV/r)- or darunavir/ritonavir (DRV/r)-based antiretroviral therapy (ART) from an older PI-based ART and those remaining on an older PI. Generalized estimating equation models were fitted to assess the association of a switch to ATV/r- or DRV/r-based ART with the rate of change in lipids, adjusted for potential confounders.

RESULTS

From 2007 to 2014, 47 PHIV children/adolescents switched to ATV/r or DRV/r, while 120 remained on an older PI [primarily lopinavir/r (72%) and nelfinavir (24%)]. Baseline age ranged from 7 to 21 years. After adjustment for age, Tanner stage, race/ethnicity, and HIV RNA level, a switch to ATV/r or DRV/r was associated with a more rapid annual rate of decline in the ratio of TC:HDL-C. (β = -0.12; P = 0.039) than remaining on an older PI. On average, TC declined by 4.57 mg/dL/year (P = 0.057) more in the switch group. A switch to ATV/r or DRV/r was not associated with the rate of HDL-C, LDL-C, or TG change.

CONCLUSIONS

A switch to ATV/r or DRV/r may result in more rapid reduction in TC and the TC:HDL-C ratio in PHIV youth, potentially impacting long-term cardiovascular disease risk.

Infection control in hospitals managing drug-resistant tuberculosis in Pakistan: how are we doing?

Setting: Ten hospitals managing drug-resistant tuberculosis (TB) in Pakistan. Objective: To assess the implementation of TB infection control (IC) practices and reasons for non-adherence to guidelines. Design: This was a descriptive study conducted between April and October 2016 with three components: 1) non-participant observation of service delivery areas (SDAs) (n = 82) in hospitals (n = 10) using structured checklists; 2) exit interviews with 100 patients (10 per hospital); and 3) interviews with 100 health-care workers (HCWs, 10/hospital). Results: Of the 82 SDAs, posters were displayed in 34 (41%), mechanical ventilation was implemented in 79% and functional ultraviolet germicidal irradiation (UVGI) was available in only 26%. Patient interviews showed 50-65% adherence to triage and use of personal protective measures. Key reasons for non-adherence were lack of adequate supplies, discomfort using N-95 masks, a lack of knowledge or training, perceived non-cooperation by patients, poor maintenance of mechanical ventilators and UVGI due to unstable electricity supply, a lack of clarity in roles (no-one designated in charge) and staff shortages and subsequent workloads. Adherence to natural ventilation usage was poor for reasons related to climate and privacy. Conclusion: Implementation of TBIC measures in hospitals was suboptimal. Urgent measures need to be put in place, including retraining of HCWs, addressing weaknesses in mask and poster supplies and constant supervision and monitoring.

Laparoscopy, computerised tomography and fluorodeoxyglucose positron emission tomography in the management of gastric and gastro-oesophageal junction cancers

BACKGROUND

The staging laparoscopy has been used in the management of gastrointestinal cancers. The aim of this study was to evaluate the role of staging laparoscopy, in comparison with computed tomography (CT) and fluorodeoxyglucose positron emission tomography (FDG-PET) imaging in staging patients with gastro-oesophageal junction (GOJ) and gastric cancers.

METHODS

The data were collected for patients between 1996 and 2013 undergoing investigation and treatment for GOJ and gastric cancers at a single institute. The pre-operative data (staging data), intraoperative details, post-operative course and follow-up were analysed for individual cases.

RESULTS

Staging laparoscopy altered management plan in 64 (17 %) of 387 patients with negative staging CT and FDG-PET scan. Twenty-seven (7 %) patients with GOJ cancer (types I, II and III) were identified with pathological intraperitoneal nodes, 15 (4 %) gastric cancer with metastatic intraperitoneal deposits and liver metastases and 3 % gastric cancers with positive ascitic fluid for cancer cells. Ten (3 %) of patients were downstaged and were offered curative resection. Patients with metastatic disease were referred for palliative chemotherapy. The overall sensitivity of staging laparoscopy in diagnosing intraabdominal pathology was 86 % in comparison with CT (81 %) and FDG-PET (78 %).

CONCLUSIONS

The diagnostic laparoscopy is useful for detecting and confirming nodal involvement and distant metastatic disease not evident on the staging CT scan and FDG-PET. This could potentially alter treatment and prognosis in patients with upper gastrointestinal cancer. The diagnostic laparoscopy should be performed as part of investigation and treatment planning for patients suffering from GOJ and gastric cancers. This can help to avoid surgery in patients with advanced disease.

Investigation of the epithelial to mesenchymal transition markers S100A4, vimentin and Snail1 in gastroesophageal junction tumors

Epithelial to mesenchymal transition (EMT) promotes tumor progression and invasion. As no study has focused on gastroesophageal junction (GEJ) tumors, the expression of three EMT-related proteins (S100A4, vimentin, and Snail1) was investigated with the aim of assessing their pathologic and prognostic significance. Resection specimens were obtained from 104 patients who underwent surgery for GEJ adenocarcinoma, without preoperative chemotherapy. Three tissue cores were obtained from each of the tumor body (TB), luminal surface (LS), and invasive edge (IE) to produce tissue microarrays, and immunohistochemical staining was performed. The microarrays were scored independently by two observers. The demographic and histopathologic details of the patients were collected. Overall positive expression was observed in 88 (S100A4, 85%), 16 (vimentin, 14%), and 92 (Snail1, 89%) tumors. Staining for S100 A4 was positive in 79 (76%) of TB, 69 (66%) of IE, and 69 (66%) of LS specimens. Staining for vimentin was positive in 7 (6%) of TB, 11 (11%) of IE, and 5 (5%) of LS specimens. Staining for Snail1 was positive in 83 (80%) of TB, 51 (49%) of IE, and 78 (75%) of LS specimens. Positive staining of TB for S100A4 (P = 0.04) and Snail1 at IE (P = 0.01) was associated with involvement of circumferential resection margins. Positive staining for S100A4 in the TB (P = 0.02) and LS (P = 0.01) was associated with poor 5-year overall survival. Vimentin had no statistically significant relationships with pathologic factors or outcome. The acquisition of mesenchymal protein S100A4 is associated with a poor prognosis in patients with GEJ tumors who undergo potentially curative surgery, and LS samples can be used to obtain prognostic information. Increased EMT-related protein expression (S100A4, Snail1) is associated with the involvement of circumferential resection margin.