• September 16 is recognized by the United Nations as the International Day for the Preservation of the Ozone Layer. This day is meant to raise awareness about the importance of protecting the ozone layer, which serves as a protective shield for Earth, preventing harmful ultraviolet (UV) radiation from reaching the planet's surface. India has been marking this occasion since 1995, and the theme for this year is "Montreal Protocol: Advancing Climate Actions."
• Ozone (O3) is a reactive gas made up of three oxygen atoms, which can occur both naturally and through human activities. It is found in the upper atmosphere (stratosphere), and the term "ozone hole" refers to regions where the ozone layer has been damaged, allowing more UV radiation to penetrate.
• The stratospheric ozone, located between 15 and 30 km above the Earth's surface, forms naturally when solar ultraviolet light interacts with molecular oxygen (O2). In contrast, ground-level ozone, found in the troposphere, primarily forms through chemical reactions involving volatile organic compounds (VOCs) and nitrogen oxides.
• Ozone depletion occurs in both hemispheres, notably over Antarctica in the Southern Hemisphere and to a lesser extent over the Arctic in the Northern Hemisphere.
• The depletion is more prominent in Antarctica, where the ozone hole is closely linked to stratospheric temperatures. When the temperature drops below -78°C, stratospheric clouds form, which exacerbates the ozone depletion.
• The size of the ozone hole over Antarctica fluctuates yearly, typically forming in August and closing by November or December. Certain industrial activities and consumer products release "halogen source gases" into the atmosphere, weakening the ozone layer by releasing chlorine and bromine.
• For example, air conditioning and refrigeration systems often contain chlorofluorocarbons (CFCs), which eventually break down in the stratosphere, releasing chlorine atoms that damage the ozone.
• Additionally, halons, used in fire extinguishers, contain bromine atoms that also contribute to ozone depletion. The Montreal Protocol plays a crucial role in regulating the global production and consumption of these harmful halogen gases generated by human activity

Why is the spread of mpox concerning?

Mpox, first identified in humans in 1970, has gained attention due to the spread of a new variant, Clade Ib. Organisms in a clade share a common evolutionary origin, and for mpox, there are two distinct clades: Clade I and Clade II, with Clade I being more severe. The Clade Ib variant appears to spread more quickly among humans than earlier variants, including transmission through sexual contact. In contrast, Clade Ia primarily originates from animals, as reported by Nature. The new variant has also impacted more women and children in African countries, raising concerns. Scientists are still investigating the factors driving this change in transmission patterns.

What vaccines are being used against mpox?

• Currently, three vaccines are available to combat mpox, all of which are modified versions of vaccinia, a live virus that was also the foundation of the smallpox vaccine. Although mpox is less severe and has lower fatality rates compared to smallpox, its rapid spread is attributed to its animal reservoirs, which smallpox lacked.
• The most widely used vaccine is Modified Vaccinia Ankara (MVA), produced by Bavarian Nordic in Denmark. This vaccine is approved for mpox by both the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA), and has been distributed in the Democratic Republic of Congo (DRC).
• Another vaccine, LC16m8, is manufactured by KM Biologics in Japan and has been approved for mpox by Japan’s regulatory body.
• The third vaccine, ACAM2000, is produced by U.S.-based Emergent BioSolutions and was recently approved for mpox by the FDA.
• In addition to these, new mpox vaccines are under development. BioNTech, a German biotech firm, has a vaccine in early clinical trials. Serum Institute of India (SII) has also announced it is working on an mpox vaccine and expects positive results within a year. Furthermore, the Indian Council of Medical Research (ICMR) has called for pharmaceutical companies and research organizations to collaborate on developing mpox vaccines and diagnostic kits on a royalty basis

Why did Africa face delays in receiving mpox vaccines?

• Mpox vaccines currently available are priced between $50 and $75 per dose, making them prohibitively expensive for many African countries, according to the World Health Organization (WHO). Consequently, these nations usually depend on donations from wealthier countries and vaccine manufacturers or on purchases facilitated by organizations like the Global Alliance for Vaccines and Immunization (Gavi) and UNICEF.
• However, Gavi and UNICEF can only procure vaccines that have received either full approval or an Emergency Use Listing from the WHO. For this approval, vaccine manufacturers must submit data on the efficacy and safety of their products. Some experts have criticized the WHO for being slow to grant these approvals.
• In response, WHO Director-General Tedros Adhanom Ghebreyesus stated that the delay was due to vaccine companies not completing the necessary documentation. He assured that once the paperwork is complete, the WHO would issue approvals within weeks and had already given Gavi and UNICEF permission to begin the procurement process in the meantime